feat(tools/cbmc): add testbench for RMI_REALM_ACTIVATE

Changes to the RMM code:
 - Set MAX_MEASUREMENT_SIZE to 8 bytes for CBMC, to be in sync with the
   'struct rmm_realm' definition in the CBMC testbench
 - Define separate RPV_SIZE value for CBMC so that struct rd fits in a
   CBMC granule
 - The vmids array should have global visibility when compiling for
   CBMC

Change-Id: I41c330c15e0e8d4fbbd506a068f9533f6a79e403
Signed-off-by: Mate Toth-Pal <mate.toth-pal@arm.com>
24 files changed