Co-Authored-By: ejtagle <ejtagle@hotmail.com>

Also simplify logic on all ARM-based interrupts. Now, it is REQUIRED to properly configure interrupt priority. USART should have highest priority, followed by Stepper, and then all others.

Some also get a `HAL_timer_interrupt_enabled` function.

* Enable hardware serial ports on LPC1768

* Fix compilation errors with other HALs

* FIx order of includes in LPC1768 HAL main.cpp

* Add support for RX_BUFFER_SIZE and TX_BUFFER_SIZE options in Configuration_adv.h

Alternative to #7882. If F_CPU is greater than 1000 it can be evenly divided by 8. Over 10000, 16; over 100000, 32; over 1 million, 64; etc.