ARM: move debug macros to common location

Based on suggestion by Russell King, create a common location for debug
macros and select the included debug macro file using config option.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index 3db960e..9874d07 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S
@@ -23,8 +23,8 @@
 #include <asm/thread_info.h>
 #include <asm/pgtable.h>
 
-#ifdef CONFIG_DEBUG_LL
-#include <mach/debug-macro.S>
+#if defined(CONFIG_DEBUG_LL) && !defined(CONFIG_DEBUG_SEMIHOSTING)
+#include CONFIG_DEBUG_LL_INCLUDE
 #endif
 
 /*