ARM: 8639/1: Define KERNEL_START and KERNEL_END

In preparation for adding CONFIG_DEBUG_VIRTUAL support, define a set of
common constants: KERNEL_START and KERNEL_END which abstract
CONFIG_XIP_KERNEL vs. !CONFIG_XIP_KERNEL. Update the code where
relevant.

Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/include/asm/memory.h

@@ -111,6 +111,13 @@
 
 #endif /* !CONFIG_MMU */
 
+#ifdef CONFIG_XIP_KERNEL
+#define KERNEL_START		_sdata
+#else
+#define KERNEL_START		_stext
+#endif
+#define KERNEL_END		_end
+
 /*
  * We fix the TCM memories max 32 KiB ITCM resp DTCM at these
  * locations