fvp_r: load, auth, and transfer from BL1 to BL33

Adding load, authentication, and transfer functionality from FVP R BL1 to
BL33, which will be the partner runtime code.

Signed-off-by: Lauren Wehrmeister <lauren.wehrmeister@arm.com>
Change-Id: I293cad09739dacac0d20dd57c1d98178dbe84d40
diff --git a/plat/arm/common/arm_bl1_fwu.c b/plat/arm/common/arm_bl1_fwu.c
index 124c1af..ce2c356 100644
--- a/plat/arm/common/arm_bl1_fwu.c
+++ b/plat/arm/common/arm_bl1_fwu.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2021, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -16,6 +16,8 @@
 #include <plat/arm/common/plat_arm.h>
 #include <plat/common/platform.h>
 
+#pragma weak bl1_plat_get_image_desc
+
 /* Struct to keep track of usable memory */
 typedef struct bl1_mem_info {
 	uintptr_t mem_base;