Keyboard: Helix serial.c, split_scom.c bug fix and update (#4191)

Keyboard: Helix serial.c, split_scom.c bug fix and update (#4191)

* helix/serial.c add support PD1,PD3,PE6 and configuration simplify

* Add comment about ATmega32U4 I2C

* Add compile time check for ATmega32U4 I2C

* change TAB code to 8 SPACE code

* Helix serial.c PORTD,PD0 test. OK

  OK PD0
  -  PD1
  OK PD2
  -  PD3
  -  PE6

* Helix serial.c PORTD,PD1 test. OK

   OK PD0
   OK PD1
   OK PD2
   -  PD3
   -  PE6

* Helix serial.c PORTD,PD3 test. OK

   OK PD0
   OK PD1
   OK PD2
   OK PD3
   -  PE6

* Helix serial.c PORTE,PD6 test. OK

   OK PD0
   OK PD1
   OK PD2
   OK PD3
   OK PE6

* Helix serial.c: PD0,PD1,PD3,PE6 all test end

* Helix serial.c: rename SOFT_SERIAL_PORT to SOFT_SERIAL_PIN

* Helix serial.c add debug code

* Helix serial.c: add transaction ID range check

* Helix serial.c debug code update

* Helix serial.c debug code update

* Helix serial.c: Strict checking of the value of tid.

* adjust the delay of serial.c

* Helix serial.c: remove debug code

* remove EXTRAFLAGS += -DCONSOLE_ENABLE from five_rows/rules.mk

tmk_core/common.mk has
 >ifeq ($(strip $(CONSOLE_ENABLE)), yes)
 >   TMK_COMMON_DEFS += -DCONSOLE_ENABLE

* Fix error handling in split_scomm.c

* add some comment to serial.c

* add some comment about SELECT_SOFT_SERIAL_SPEED