🐛 Fixes for BTT Octopus (#22314)

buildroot/share/PlatformIO/variants/MARLIN_BIGTREE_OCTOPUS_V1/PeripheralPins.c

 const PinMap PinMap_UART_TX[] = {
   //  {PA_0,  UART4,   STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_UART4)},
   //  {PA_2,  USART2,  STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART2)},
+  {PD_5,  USART2,  STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART2)},
   {PA_9,  USART1,  STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART1)},
   {PD_8,  USART3,  STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART3)},
   //  {PB_6,  USART1,  STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART1)},
 const PinMap PinMap_UART_RX[] = {
   //  {PA_1,  UART4,   STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_UART4)},
   //  {PA_3,  USART2,  STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART2)},
+  {PD_6,  USART2,  STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART2)},
   {PA_10, USART1,  STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART1)},
   {PD_9,  USART3,  STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART3)},
   //  {PB_7,  USART1,  STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART1)},

buildroot/share/PlatformIO/variants/MARLIN_BIGTREE_OCTOPUS_V1/variant.h

 
 // PWM resolution
 //#define PWM_RESOLUTION          12
-#define PWM_FREQUENCY           20000 // >= 20 Khz => inaudible noise for fans
+#define PWM_FREQUENCY           1000 // >= 20 Khz => inaudible noise for fans
 #define PWM_MAX_DUTY_CYCLE      255
 
 // SPI Definitions