[Keyboard] Refactor HB85 to get rid of custom i2c code (#5570)

* remove dependency on custom i2c code

* missed a pragma once

* fix readme install instructions

* config.h cleanup

* make the bootmagic key not the same bmc reset key

* disable bootmagic functionality as it doesn't seem to work on atmega32a bmc boards

keyboards/gray_studio/hb85/rules.mk

@@ -31,7 +31,7 @@ F_CPU = 12000000
 BOOTLOADER = bootloadHID
 
 # build options
-BOOTMAGIC_ENABLE = lite
+BOOTMAGIC_ENABLE = no
 MOUSEKEY_ENABLE = no
 EXTRAKEY_ENABLE = yes
 CONSOLE_ENABLE = yes
@@ -42,7 +42,7 @@ RGBLIGHT_CUSTOM_DRIVER = yes
 
 OPT_DEFS = -DDEBUG_LEVEL=0
 
-SRC += i2c.c
+SRC += i2c_master.c
 
 # programming options
 PROGRAM_CMD = ./util/atmega32a_program.py $(TARGET).hex