fix(mpam): renamed ENABLE_MPAM_FOR_LOWER_ELS to ENABLE_FEAT_MPAM

Renaming ENABLE_MPAM_FOR_LOWER_ELS to ENABLE_FEAT_MPAM for uniformity
with other feature enablement build flags

Signed-off-by: Arvind Ram Prakash <arvind.ramprakash@arm.com>
Change-Id: Ib5044a480ebd1e31260c3ce6a462ba51cb3ccdba
2 files changed