fix(ras): remove RAS_FFH_SUPPORT and introduce FFH_SUPPORT

This patch removes RAS_FFH_SUPPORT macro which is the combination of
ENABLE_FEAT_RAS and HANDLE_EA_EL3_FIRST_NS. Instead introduce an
internal macro FFH_SUPPORT which gets enabled when platforms wants
to enable lower EL EA handling at EL3. The internal macro FFH_SUPPORT
will be automatically enabled if HANDLE_EA_EL3_FIRST_NS is enabled.
FFH_SUPPORT along with ENABLE_FEAT_RAS will be used in source files
to provide equivalent check which was provided by RAS_FFH_SUPPORT
earlier. In generic code we needed a macro which could abstract both
HANDLE_EA_EL3_FIRST_NS and RAS_FFH_SUPPORT macros that had limitations.
Former was tied up with NS world only while the latter was tied to RAS
feature.

This is to allow Secure/Realm world to have their own FFH macros
in future.

Signed-off-by: Manish Pandey <manish.pandey2@arm.com>
Change-Id: Ie5692ccbf462f5dcc3f005a5beea5aa35124ac73
diff --git a/include/lib/el3_runtime/aarch64/context.h b/include/lib/el3_runtime/aarch64/context.h
index fb28505..47d91de 100644
--- a/include/lib/el3_runtime/aarch64/context.h
+++ b/include/lib/el3_runtime/aarch64/context.h
@@ -71,7 +71,7 @@
  * KFH mode : Used as counter value
  */
 #define CTX_NESTED_EA_FLAG	U(0x48)
-#if HANDLE_EA_EL3_FIRST_NS
+#if FFH_SUPPORT
  #define CTX_SAVED_ESR_EL3	U(0x50)
  #define CTX_SAVED_SPSR_EL3	U(0x58)
  #define CTX_SAVED_GPREG_LR	U(0x60)