feat(measured-boot): introduce platform function to measure and publish Public Key

Added a platform function to measure and publish Public Key information.
Subsequent patches define this function for the FVP and TC platforms to
measure Public Key and publishes it to RSS if MEASURED_BOOT is
enabled.

Change-Id: I1f61f44c7a83bb4cbafbd1af97b5adeb8398e8e8
Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
1 file changed