feat(spmc): enable building of the SPMC at EL3

Introduce build flag for enabling the secure partition
manager core, SPMC_AT_EL3. When enabled, the SPMC module
will be included into the BL31 image. By default the
flag is disabled.

Signed-off-by: Marc Bonnici <marc.bonnici@arm.com>
Change-Id: I5ea1b953e5880a07ffc91c4dea876a375850cf2a
diff --git a/bl31/bl31.mk b/bl31/bl31.mk
index 7d83e3c..214cf2f 100644
--- a/bl31/bl31.mk
+++ b/bl31/bl31.mk
@@ -25,6 +25,14 @@
 
 include lib/extensions/amu/amu.mk
 include lib/mpmm/mpmm.mk
+
+ifeq (${SPMC_AT_EL3},1)
+  $(warning "EL3 SPMC is an experimental feature")
+  $(info Including EL3 SPMC makefile)
+  include services/std_svc/spm/common/spm.mk
+  include services/std_svc/spm/el3_spmc/spmc.mk
+endif
+
 include lib/psci/psci_lib.mk
 
 BL31_SOURCES		+=	bl31/bl31_main.c				\
@@ -42,6 +50,7 @@
 				${PSCI_LIB_SOURCES}				\
 				${SPMD_SOURCES}					\
 				${SPM_MM_SOURCES}				\
+				${SPMC_SOURCES}					\
 				${SPM_SOURCES}
 
 ifeq (${DISABLE_MTPMU},1)