mem_protect: Fix PSCI FEATURES API for MEM_PROTECT_CHECK

With this patch the PSCI_FEATURES API correctly reports availability
of the PSCI_MEM_PROTECT_CHECK API - PSCI_MEM_CHK_RANGE_AARCH64 is
added to the PSCI capabilities mask, PSCI_CAP_64BIT_MASK

Change-Id: Ic90ee804deaadf0f948dc2d46ac5fe4121ef77ae
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>

lib/psci/psci_private.h

@@ -90,7 +90,8 @@
 			define_psci_cap(PSCI_SYSTEM_SUSPEND_AARCH64) |	\
 			define_psci_cap(PSCI_STAT_RESIDENCY_AARCH64) |	\
 			define_psci_cap(PSCI_STAT_COUNT_AARCH64) |	\
-			define_psci_cap(PSCI_SYSTEM_RESET2_AARCH64))
+			define_psci_cap(PSCI_SYSTEM_RESET2_AARCH64) |	\
+			define_psci_cap(PSCI_MEM_CHK_RANGE_AARCH64))
 
 /*
  * Helper macros to get/set the fields of PSCI per-cpu data.