feat(rmmd): add support for RMM Boot interface

This patch adds the infrastructure needed to pass boot arguments from
EL3 to RMM and allocates a shared buffer between both worlds that can
be used, among others, to pass a boot manifest to RMM. The buffer is
composed a single memory page be used by a later EL3 <-> RMM interface
by all CPUs.

The RMM boot manifest is not implemented by this patch.

In addition to that, this patch also enables support for RMM when
RESET_TO_BL31 is enabled.

Signed-off-by: Javier Almansa Sobrino <javier.almansasobrino@arm.com>
Change-Id: I855cd4758ee3843eadd9fb482d70a6d18954d82a
diff --git a/include/plat/common/platform.h b/include/plat/common/platform.h
index b62a631..479a48b 100644
--- a/include/plat/common/platform.h
+++ b/include/plat/common/platform.h
@@ -305,11 +305,11 @@
 /*******************************************************************************
  * Mandatory BL31 functions when ENABLE_RME=1
  ******************************************************************************/
-int plat_get_cca_attest_token(uintptr_t buf, size_t *len,
-			       uintptr_t hash, size_t hash_size);
-int plat_get_cca_realm_attest_key(uintptr_t buf, size_t *len,
-				   unsigned int type);
-
+int plat_rmmd_get_cca_attest_token(uintptr_t buf, size_t *len,
+				   uintptr_t hash, size_t hash_size);
+int plat_rmmd_get_cca_realm_attest_key(uintptr_t buf, size_t *len,
+				       unsigned int type);
+size_t plat_rmmd_get_el3_rmm_shared_mem(uintptr_t *shared);
 /*******************************************************************************
  * Optional BL31 functions (may be overridden)
  ******************************************************************************/