feat(handoff): add AArch32 handoff support

Add support for testing firmware handoff in AArch32 mode. This requires
some tweaks to enable the boot args from TF-A to be stashed for later
use.

Change-Id: Ib1b88688b6229b10020c936319605c7ed6307ca2
Signed-off-by: Harrison Mutai <harrison.mutai@arm.com>
2 files changed