Support shared Mbed TLS heap for SGM

Change-Id: Ibbfedb6601feff51dfb82c1d94850716c5a36d24
Signed-off-by: John Tsichritzis <john.tsichritzis@arm.com>
diff --git a/plat/arm/css/sgm/sgm_mmap_config.c b/plat/arm/css/sgm/sgm_mmap_config.c
index 009ee64..8a4a8ab 100644
--- a/plat/arm/css/sgm/sgm_mmap_config.c
+++ b/plat/arm/css/sgm/sgm_mmap_config.c
@@ -43,6 +43,9 @@
 #ifdef SPD_opteed
 	ARM_OPTEE_PAGEABLE_LOAD_MEM,
 #endif
+#if TRUSTED_BOARD_BOOT && LOAD_IMAGE_V2 && !BL2_AT_EL3
+	ARM_MAP_BL1_RW,
+#endif
 	{0}
 };
 #endif