refactor(cpufeat): align FEAT_SEL2 to new feature handling

In ARMv8.4, the EL2 exception level got added to the secure world.
Adapt and rename the existing is_armv8_4_sel2_present() function, to
align its handling with the other CPU features.

Change-Id: If11e1942fdeb63c63f36ab9e89be810347d1a952
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
5 files changed