Crypto: Remove workaround for CFB tests in CC-312 enabled platforms

The workaround based on compiler defines to disable CFB on CC-312
enabled platforms is not required anymore as now the tests are
completely controlled through cmake configuration options available
in the platforms port on TF-M.

Signed-off-by: Antonio de Angelis <antonio.deangelis@arm.com>
Change-Id: I1ff29d8585f845a6dbbcd6edb2e97a11fd4a1c08
1 file changed