update stm32f4 stdlibrary and cmsis

Signed-off-by: Stefan Guelland <stefan@sguelland.de>
seperate stm32f4 discovery from stm32f4 discovery expansion board

Signed-off-by: Stefan Guelland <stefan@sguelland.de>
add const to constant filds

Signed-off-by: Stefan Guelland <stefan@sguelland.de>
improve port macros for different endians

Signed-off-by: Stefan Guelland <stefan@sguelland.de>