refactor: rename RAS_EXTENSION to FEAT_RAS

The existing RAS_EXTENSION is now divided in two options
1. ENABLE_FEAT_RAS: to check RAS arch feature
2. RAS_FFH_SUPPORT: Handling of RAS errors in Firmware first

Modify CI scripts to reflect this change in TF-A.

Signed-off-by: Manish Pandey <manish.pandey2@arm.com>
Change-Id: Iaed189d98ddbafc92066b593fc70cd5ead9f604c
2 files changed