Clean usage of void pointers to access symbols

Void pointers have been used to access linker symbols, by declaring an
extern pointer, then taking the address of it. This limits symbols
values to aligned pointer values. To remove this restriction an
IMPORT_SYM macro has been introduced, which declares it as a char
pointer and casts it to the required type.

Change-Id: I89877fc3b13ed311817bb8ba79d4872b89bfd3b0
Signed-off-by: Joel Hutton <Joel.Hutton@Arm.com>
diff --git a/plat/hisilicon/poplar/bl1_plat_setup.c b/plat/hisilicon/poplar/bl1_plat_setup.c
index 3955113..25eed59 100644
--- a/plat/hisilicon/poplar/bl1_plat_setup.c
+++ b/plat/hisilicon/poplar/bl1_plat_setup.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2017-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -23,13 +23,6 @@
 #include "hi3798cv200.h"
 #include "plat_private.h"
 
-/* Symbols from link script for conherent section */
-extern unsigned long __COHERENT_RAM_START__;
-extern unsigned long __COHERENT_RAM_END__;
-
-#define BL1_COHERENT_RAM_BASE	(unsigned long)(&__COHERENT_RAM_START__)
-#define BL1_COHERENT_RAM_LIMIT	(unsigned long)(&__COHERENT_RAM_END__)
-
 /* Data structure which holds the extents of the trusted RAM for BL1 */
 static meminfo_t bl1_tzram_layout;
 
@@ -92,8 +85,8 @@
 			       bl1_tzram_layout.total_size,
 			       BL1_RO_BASE, /* l-loader and BL1 ROM */
 			       BL1_RO_LIMIT,
-			       BL1_COHERENT_RAM_BASE,
-			       BL1_COHERENT_RAM_LIMIT);
+			       BL_COHERENT_RAM_BASE,
+			       BL_COHERENT_RAM_END);
 }
 
 void bl1_platform_setup(void)