linker_script: move stacks section to bl_common.ld.h

The stacks section is the same for all BL linker scripts.

Move it to the common header file.

Change-Id: Ibd253488667ab4f69702d56ff9e9929376704f6c
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/bl32/sp_min/sp_min.ld.S b/bl32/sp_min/sp_min.ld.S
index da005db..8e91cec 100644
--- a/bl32/sp_min/sp_min.ld.S
+++ b/bl32/sp_min/sp_min.ld.S
@@ -101,12 +101,7 @@
     ASSERT(. <= BL32_PROGBITS_LIMIT, "BL32 progbits has exceeded its limit.")
 #endif
 
-    stacks (NOLOAD) : {
-        __STACKS_START__ = .;
-        *(tzfw_normal_stacks)
-        __STACKS_END__ = .;
-    } >RAM
-
+    STACK_SECTION >RAM
     BSS_SECTION >RAM
     XLAT_TABLE_SECTION >RAM