refactor(measured-boot): change all occurrences of RSS to RSE

Changes all occurrences of "RSS" and "rss" in the code and build files
to "RSE" and "rse".

Signed-off-by: Tamas Ban <tamas.ban@arm.com>
Change-Id: I8c2fcbdf1de1c75f9969d28bc15e0b3500071404
5 files changed