This adds the necessary bits for linker scripts and source code
to specify which symbols are needed for boot process so they
can be grouped together.
One use of this is to group boot related code and data so these
won't interval with other kernel and application for better
caching.
This is a must for demand paging as some functions and data
must be available during the boot process and before the memory
manager is initialized. During this time, paging cannot be used
so symbols linked in virtual memory space are unavailable.
This is up to the arch/SoC/board to define the sections in
their linker scripts as section may need special alignment
which cannot be done in common script snippets.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
d812728ec4