Add Satisfaction75 to QMK, Enable EEPROM on stm32f072 (#5094)

* Add stm32f072 base ck4x4 to handwired

* add prints

* Save these tries

* Save changes again

* Working hadron oled

* OLEd working but ws2812b still iffy:

* save another try

* Encoder feature + OLED

* RTC code

* Implement clock setting mode

* Whitespace

* Encoder hooked up to working LED PWM code

* Add missing files

* eeprom changes

* Save changes

* Move i2c master

* Move satisfaction75 under cannonkeys

* Set proper default folder

* Revert some core changes

* Undo paved iris changes

* Reorganize code for maintainability and prep for new features

* Add starting code for clock OLED mode

* Clock set mode finished

* Add custom encoder modes

* Actually add VIA keymap

* Gate to only 072

* fix gate for only 072

* Update header guards and includes

* Update i2c selection strategy

* Update board.c to handle software reset to DFU

keyboards/handwired/ck4x4/rules.mk

@@ -0,0 +1,49 @@
+# project specific files
+# SRC =	matrix.c \
+# 	    led.c
+
+## chip/board settings
+# the next two should match the directories in
+#  <chibios>/os/hal/ports/$(MCU_FAMILY)/$(MCU_SERIES)
+MCU_FAMILY = STM32
+MCU_SERIES = STM32F0xx
+# linker script to use
+# it should exist either in <chibios>/os/common/ports/ARMCMx/compilers/GCC/ld/
+#  or <this_dir>/ld/
+MCU_LDSCRIPT = STM32F072xB
+# startup code to use
+# is should exist in <chibios>/os/common/ports/ARMCMx/compilers/GCC/mk/
+MCU_STARTUP = stm32f0xx
+# it should exist either in <chibios>/os/hal/boards/
+#  or <this_dir>/boards
+BOARD = ST_STM32F072B_DISCOVERY
+# Cortex version
+# Teensy LC is cortex-m0; Teensy 3.x are cortex-m4
+MCU  = cortex-m0
+# ARM version, CORTEX-M0/M1 are 6, CORTEX-M3/M4/M7 are 7
+ARMV = 6
+# If you want to be able to jump to bootloader from firmware on STM32 MCUs,
+# set the correct BOOTLOADER_ADDRESS. Either set it here, or define it in
+# ./bootloader_defs.h or in ./boards/<FOO>/bootloader_defs.h (if you have
+# a custom board definition that you plan to reuse).
+# If you're not setting it here, leave it commented out.
+# It is chip dependent, the correct number can be looked up here (page 175):
+# http://www.st.com/web/en/resource/technical/document/application_note/CD00167594.pdf
+# This also requires a patch to chibios:
+#   <tmk_dir>/tmk_core/tool/chibios/ch-bootloader-jump.patch
+#STM32_BOOTLOADER_ADDRESS = 0x1FFFC800
+
+# Build Options
+#   comment out to disable the options.
+#
+
+#BOOTMAGIC_ENABLE = yes	# Virtual DIP switch configuration
+MOUSEKEY_ENABLE = yes	# Mouse keys
+EXTRAKEY_ENABLE = yes	# Audio control and System control
+CONSOLE_ENABLE = yes	# Console for debug
+COMMAND_ENABLE = yes    # Commands for debug and configuration
+SLEEP_LED_ENABLE = yes  # Breathing sleep LED during USB suspend
+NKRO_ENABLE = yes	    # USB Nkey Rollover
+CUSTOM_MATRIX = no # Custom matrix file
+
+DEFAULT_FOLDER = handwired/ck4x4