Best way to enable MBED_DEPRICATED APIs to be properly rendered
requires using the doxygen preprocessor. This means all device_has
labels need to also be defined or the default DOXYGEN_ONLY label
applied to the API headers which this commit does. ASYNCH currently
exluded.
stop using scope for \addtogroup. It was placing class methods into the
group documentation instead of the class documentation. The new style is
to explicitly tag the class as @ingroup. This new method will allow the
class to be linked in the group page, and the class page will contain
the detailed documentation of the class methods.
Flash IAP that provides erase/read/program to an internal API. It
invokes flash HAL functions.
FlashIAP checks for alignments for erase and program. HAL functions
do not, to avoid duplication per target implementation.