chore: Initial commit (blinky)

cubemx/Core/Src/CMakeLists.txt

@@ -0,0 +1,12 @@
+target_sources(cubemx PRIVATE
+	gpio.c
+	i2c.c
+	main.c
+	stm32f4xx_hal_msp.c
+	stm32f4xx_hal_timebase_tim.c
+	stm32f4xx_it.c
+	syscalls.c
+	sysmem.c
+	system_stm32f4xx.c
+	usart.c
+)