feat(fvp): add crypto support in BL31

DRTM implementation needs crypto support in BL31 to calculate
hash of various DRTM components

Signed-off-by: Manish V Badarkhe <manish.badarkhe@arm.com>
Change-Id: I659ce8e54550946db253d23f150cca8b2fa7b880
3 files changed