Update (c) comments (#14584)

Marlin/src/HAL/HAL_STM32/pinsDebug_STM32GENERIC.h

 /**
  * Marlin 3D Printer Firmware
- * Copyright (C) 2019 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ * Copyright (c) 2019 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by

Marlin/src/HAL/HAL_STM32/pinsDebug_STM32duino.h

 /**
  * Marlin 3D Printer Firmware
- * Copyright (C) 2019 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ * Copyright (c) 2019 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by

Marlin/src/module/thermistor/thermistor_512.h

 /**
  * Marlin 3D Printer Firmware
- * Copyright (C) 2019 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ * Copyright (c) 2019 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
  *
  * Based on Sprinter and grbl.
- * Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by

Marlin/src/pins/mega/pins_WANHAO_ONEPLUS.h

 /**
  * Marlin 3D Printer Firmware
- * Copyright (C) 2016 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ * Copyright (c) 2019 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
  *
  * Based on Sprinter and grbl.
- * Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by

Marlin/src/pins/stm32/pins_BIGTREE_SKR_MINI_E3.h

 /**
  * Marlin 3D Printer Firmware
- * Copyright (C) 2019 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ * Copyright (c) 2019 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
  *
  * Based on Sprinter and grbl.
- * Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by

Marlin/src/sd/usb_flashdrive/Sd2Card_FlashDrive.cpp

 /**
  * Marlin 3D Printer Firmware
- * Copyright (C) 2019 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ * Copyright (c) 2019 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
  *
  * Based on Sprinter and grbl.
- * Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by

Marlin/src/sd/usb_flashdrive/Sd2Card_FlashDrive.h

 /**
  * Marlin 3D Printer Firmware
- * Copyright (C) 2019 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ * Copyright (c) 2019 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
  *
  * Based on Sprinter and grbl.
- * Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by

config/examples/Creality/CR-20 Pro/_Statusscreen.h

 /**
  * Marlin 3D Printer Firmware
- * Copyright (C) 2019 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ * Copyright (c) 2019 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
  *
  * Based on Sprinter and grbl.
- * Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by

config/examples/Creality/Ender-5/_Bootscreen.h

 /**
  * Marlin 3D Printer Firmware
- * Copyright (C) 2019 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ * Copyright (c) 2019 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
  *
  * Based on Sprinter and grbl.
- * Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by

config/examples/Creality/Ender-5/_Statusscreen.h

 /**
  * Marlin 3D Printer Firmware
- * Copyright (C) 2019 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ * Copyright (c) 2019 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
  *
  * Based on Sprinter and grbl.
- * Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by