cactus: test SP-to-SP memory share operations

Handle 'CACTUS_REQ_MEM_SEND_CMD' by sending memory to the receiver SP.

Signed-off-by: J-Alves <joao.alves@arm.com>
Change-Id: I4ca1ff91c52640f3a7204cc63041a091c210d8b7
diff --git a/spm/cactus/cactus_ffa_tests.c b/spm/cactus/cactus_ffa_tests.c
index 07aaaca..5863456 100644
--- a/spm/cactus/cactus_ffa_tests.c
+++ b/spm/cactus/cactus_ffa_tests.c
@@ -307,7 +307,11 @@
 			m->receivers[0].receiver_permissions.permissions),
 		FFA_DATA_ACCESS_RW);
 
-	mem_attrs = MT_RW_DATA | MT_NS | MT_EXECUTE_NEVER;
+	mem_attrs = MT_RW_DATA | MT_EXECUTE_NEVER;
+
+	if (!IS_SP_ID(sender)) {
+		mem_attrs |= MT_NS;
+	}
 
 	ret = mmap_add_dynamic_region(
 			(uint64_t)composite->constituents[0].address,