The BSPs provide memory for the separate C Program Heap initialization
via _Memory_Get(). Most BSPs provide exactly one memory area. Only two
BSPs provide more than one memory area (arm/altera-cyclone-v and
bsps/powerpc/mpc55xxevb). Only if more than one memory area is
provided, there is a need to use _Heap_Extend(). Provide two
implementations to initialize the separate C Program Heap and let the
BSP select one of the implementations based on the number of provided
memory areas. This gets rid of a dependency on _Heap_Extend(). It
also avoids dead code sections for most BSPs.
Change licence to BSD-2-Clause according to file history.
Update #3053.
