feat(rmm-eac4): modify RSI_ATTESTATION_TOKEN commands

Modifies RSI_ATTESTATION_TOKEN_INIT and
RSI_ATTESTATION_TOKEN_CONTINUE commands as per
RMM Specification 1.0-eac4.
Number of 4K pages allocated for attestation
buffer is defined by RMM_ATTEST_BUFFER_PAGES
in CommonConfigs.cmake and set to 1 by default.

Signed-off-by: AlexeiFedorov <Alexei.Fedorov@arm.com>
Change-Id: Icda7f26e291a19b143ae14a291c03cc7bda0e076
diff --git a/cmake/CommonConfigs.cmake b/cmake/CommonConfigs.cmake
index 7e1e9a4..d212c06 100644
--- a/cmake/CommonConfigs.cmake
+++ b/cmake/CommonConfigs.cmake
@@ -53,6 +53,15 @@
     ELSE OFF)
 
 #
+# The number of 4K pages allocated for attestation buffer.
+#
+arm_config_option(
+    NAME RMM_CCA_TOKEN_BUFFER
+    HELP "Number of pages to allocate in Aux granules for Realm CCA token"
+    TYPE STRING
+    DEFAULT 1)
+
+#
 # Introduce a pseudo-library purely for applying flags to RMM's libraries.
 # This is applied to any targets created after this point.
 #
@@ -91,6 +100,9 @@
         INTERFACE "RMM_FPU_USE_AT_REL2=1")
 endif()
 
+target_compile_definitions(rmm-common
+    INTERFACE "RMM_CCA_TOKEN_BUFFER=U(${RMM_CCA_TOKEN_BUFFER})")
+
 #
 # Project name and version
 #