Add linker symbol declarations to bl_common.h

Add extern declarations of linker symbols to bl_common.h. These are
used by platform ports to determine the memory layout of BL images.
Adding the declarations to this file facilitates removal of these
declarations from the platform porting source files in subsequent
patches.

Also remove the linker symbol declarations from common TSP source
code.

Change-Id: I8ed0426bc815317c4536b588e4e78bc15b4fe91c
diff --git a/bl32/tsp/tsp_main.c b/bl32/tsp/tsp_main.c
index d8895b2..2a4ce4f 100644
--- a/bl32/tsp/tsp_main.c
+++ b/bl32/tsp/tsp_main.c
@@ -38,12 +38,6 @@
 #include <tsp.h>
 #include "tsp_private.h"
 
-/*******************************************************************************
- * Declarations of linker defined symbols which will help us find the layout
- * of trusted SRAM
- ******************************************************************************/
-extern unsigned long __RO_START__;
-extern unsigned long __BL32_END__;
 
 /*******************************************************************************
  * Lock to control access to the console
diff --git a/include/common/bl_common.h b/include/common/bl_common.h
index b36c9d3..33b75f1 100644
--- a/include/common/bl_common.h
+++ b/include/common/bl_common.h
@@ -110,6 +110,26 @@
 
 #define ARRAY_SIZE(a)	(sizeof(a) / sizeof((a)[0]))
 
+/*
+ * Declarations of linker defined symbols to help determine memory layout of
+ * BL images
+ */
+extern unsigned long __RO_START__;
+extern unsigned long __RO_END__;
+#if IMAGE_BL2
+extern unsigned long __BL2_END__;
+#elif IMAGE_BL31
+extern unsigned long __BL31_END__;
+#elif IMAGE_BL32
+extern unsigned long __BL32_END__;
+#endif /* IMAGE_BLX */
+
+#if USE_COHERENT_MEM
+extern unsigned long __COHERENT_RAM_START__;
+extern unsigned long __COHERENT_RAM_END__;
+#endif
+
+
 /*******************************************************************************
  * Structure used for telling the next BL how much of a particular type of
  * memory is available for its use and how much is already used.