ci(coverity): add coverage for FEAT_TCR2

This patch adds a build config for FEAT_TCR2 to tf-cov-make,
to ensure that the relevant code and files are scanned.

Signed-off-by: Jayanth Dodderi Chidanand <jayanthdodderi.chidanand@arm.com>
Change-Id: I97c439bfac74e35daa9b94e94281c4a7b19af052
1 file changed