feat(mte): build secure targets with MTE enabled

Enable Memory Tagging Extension for secure targets. The option results
in compile flag -march=armv8.5-a+mte and -fsanitize=memtag being added.

Signed-off-by: Maksims Svecovs <maksims.svecovs@arm.com>
Change-Id: Id4fcf6d04c8e85d138b874ba7de05028ddab8d84
1 file changed