[Keyboard] Refactor jj40 to current standards (#5574)

* Refactor jj40 in line with current ps2avrgb template

* Disable bootmagic lite as it seems to not work on atmega32a/bootloadHID

* Add backlight pwm bodge till #4324 lands

* Increase planck keymap compatibility

quantum/quantum.c

@@ -1125,6 +1125,13 @@ static const uint8_t backlight_pin = BACKLIGHT_PIN;
 #  define COMxx1 COM1A1
 #  define OCRxx  OCR3A
 #  define ICRx   ICR3
+#elif defined(__AVR_ATmega32A__) && BACKLIGHT_PIN == D4
+#  define TCCRxA TCCR1A
+#  define TCCRxB TCCR1B
+#  define COMxx1 COM1B1
+#  define OCRxx  OCR1B
+#  define ICRx   ICR1
+#  define TIMSK1 TIMSK
 #else
 #  define NO_HARDWARE_PWM
 #endif