cactus: break the message loop on bad message request

When the FF-A direct message request is not received as expected
prefer breaking the message loop and panicing rather than replying
with the FF-A error ABI to the SPMC. It is improper to use this
latter ABI in context of Hafnium as this is treated as an invalid
SMC issued by the SP.

Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
Change-Id: I77cd0831a850e775f9996f4ecd1b5a81e6244a53
1 file changed