First add the flash_data.h that describe the flash memory topology,
and also activate FLASH support for the corresponding targets.
This is a 1,5MB flash memory device which contains 15 sectors, where
sectors 12 to 15 are 128KB sectors. So flash_api.c needed has been
updated to differentiate between this flash memory and the 2MB ones
by checking existence of sector 16 instead of sector 12.