Set STM32 MCU speed through the MCU_SPEED setting

Author: mean

Platform/Core/BoardFlags/CompilerFlagsSetterStm32.cmake

@@ -8,7 +8,9 @@ ELSE(TRY_CPU_FLAGS)
     _get_board_property(${BOARD_ID} build.cpu_flags CPU_FLAGS)
 ENDIF(TRY_CPU_FLAGS)
 
-set(COMPILE_FLAGS "-DF_CPU=${FCPU} ${CPU_FLAGS} -DARDUINO=${NORMALIZED_SDK_VERSION} ")
+# dont set the mcu speed, it is done elsewhere
+# set(COMPILE_FLAGS "-DF_CPU=${FCPU} ${CPU_FLAGS} -DARDUINO=${NORMALIZED_SDK_VERSION} ")
+ set(COMPILE_FLAGS " ${CPU_FLAGS} -DARDUINO=${NORMALIZED_SDK_VERSION} ")
 # This should be derived from the arduino config files
 # hardcode them for the moment
 

Platform/Initialization/DefaultCFlagsStm32.cmake

@@ -7,8 +7,12 @@ ENDIF(NOT DEFINED ARDUINO_UPLOAD_METHOD)
 
 IF(NOT DEFINED ARDUINO_CFLAGS_SET)
     SET(DEFINED ARDUINO_CFLAGS_SET 1)
+    IF(NOT DEFINED MCU_SPEED )
+        SET(MCU_SPEED 72000000L)
+    ENDIF(NOT DEFINED MCU_SPEED )
+    
     SET(ARDUINO_DEFAULT_CFLAGS " -ffunction-sections -fdata-sections -nostdlib --param max-inline-insns-single=500  -w   -mcpu=cortex-m3  -mthumb   -g ")
-    SET(ARDUINO_DEFAULT_CFLAGS " ${ARDUINO_DEFAULT_CFLAGS}  -DGENERIC_BOOTLOADER -DF_CPU=72000000L  -DARDUINO_ARCH_STM32F1 -DCONFIG_MAPLE_MINI_NO_DISABLE_DEBUG    ")
+    SET(ARDUINO_DEFAULT_CFLAGS " ${ARDUINO_DEFAULT_CFLAGS}  -DGENERIC_BOOTLOADER -DF_CPU=${MCU_SPEED}L  -DARDUINO_ARCH_STM32F1 -DCONFIG_MAPLE_MINI_NO_DISABLE_DEBUG    ")
     #SET(ARDUINO_DEFAULT_CFLAGS " ${ARDUINO_DEFAULT_CFLAGS}  -DF_CPU=72000000L  -DARDUINO_ARCH_STM32F1 ")
 
     SET(ARDUINO_DEFAULT_CXXFLAGS "${ARDUINO_DEFAULT_CFLAGS} -fno-rtti  -fno-exceptions -std=gnu++11   -Werror=return-type")