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/docs/components/ras.rst b/docs/components/ras.rst
index 8d00345..e237ebb 100644
--- a/docs/components/ras.rst
+++ b/docs/components/ras.rst
@@ -63,17 +63,19 @@
 TF-A build options
 ==================
 
-- **ENABLE_FEAT_RAS**: Manage FEAT_RAS extension when switching the world.
-- **RAS_FFH_SUPPORT**: Pull in necessary framework and platform hooks for Firmware first
-  handling(FFH) of RAS errors.
+- **ENABLE_FEAT_RAS**: Enable RAS extension feature at EL3.
+- **HANDLE_EA_EL3_FIRST_NS**: Required for FFH
 - **RAS_TRAP_NS_ERR_REC_ACCESS**: Trap Non-secure access of RAS error record registers.
-- **RAS_EXTENSION**: Deprecated macro, equivalent to ENABLE_FEAT_RAS and RAS_FFH_SUPPORT
-  put together.
+- **RAS_EXTENSION**: Deprecated macro, equivalent to ENABLE_FEAT_RAS and
+  HANDLE_EA_EL3_FIRST_NS put together.
+
+RAS internal macros
+
+- **FFH_SUPPORT**: Gets enabled if **HANDLE_EA_EL3_FIRST_NS** is enabled.
 
 RAS feature has dependency on some other TF-A build flags
 
 - **EL3_EXCEPTION_HANDLING**: Required for FFH
-- **HANDLE_EA_EL3_FIRST_NS**: Required for FFH
 - **FAULT_INJECTION_SUPPORT**: Required for testing RAS feature on fvp platform
 
 RAS Framework
@@ -238,7 +240,7 @@
 Enabling RAS support is a platform choice
 
 The RAS support in |TF-A| introduces a default implementation of
-``plat_ea_handler``, the External Abort handler in EL3. When ``RAS_FFH_SUPPORT``
+``plat_ea_handler``, the External Abort handler in EL3. When ``ENABLE_FEAT_RAS``
 is set to ``1``, it'll first call ``ras_ea_handler()`` function, which is the
 top-level RAS exception handler. ``ras_ea_handler`` is responsible for iterating
 to through platform-supplied error records, probe them, and when an error is