feat(arm): support AArch32 booting with handoff

Configre SP-MIN to receive information via the firmare handoff
framework. In BL1 and BL2, select the 32-bit variants of the SRAM layout
and entry point info to enable booting in aarch32 mode. In SP-MIN
process expected data directly from the transfer list in secure memory.

Change-Id: If0417cdd4c47b772332eb6fd4b71ef0ea474f0fa
Signed-off-by: Harrison Mutai <harrison.mutai@arm.com>
5 files changed