feat(smccc): add FEAT_TWED to ARCH_FEATURE_AVAILABILITY

FEAT_TWED (Delayed Trapping of WFE) is an ARMv8.6 feature that is
advertised in the ID_AA64MMFR1_EL1 ID register and controlled by a bit
in the SCR_EL3 register.

On cores implementing that feature we should announce it in the
ARCH_FEATURE_AVAILABILITY SMCCC call, so that users of that interface
can correctly assess the availability of the delayed trap.

Change-Id: I2b185f7eb9d58e45472983204db0305511372477
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
1 file changed