MIPS: XBurst: suitable solution for per-board debug_ll

In the commit 40492a0c13
(MIPS: add common header file for DEBUG_LL via NS16550)
introduced common DEBUG_LL via NS16550 for MIPS
(see file arch/mips/include/debug_ll_ns16550.h).

In the commit 1cbe2b2c00
(MIPS: XBurst: add Ritmix RZX-50 board support)
the file debug_ll_ns16550.h used in
the file arch/mips/mach-xburst/include/mach/debug_ll.h.

Usage looks like this:

------------------------------------------------
+#ifdef CONFIG_BOARD_RZX50
+#include <mach/debug_ll_jz4755.h>
+#endif
+
+#include <debug_ll_ns16550.h>
------------------------------------------------

So after adding another board (e.g. A320) we will have something like this:

------------------------------------------------
 #ifdef CONFIG_BOARD_RZX50
 #include <mach/debug_ll_jz4755.h>
 #endif

+#ifdef CONFIG_BOARD_A320
+#include <mach/debug_ll_jz4740.h>
+#endif

 #include <debug_ll_ns16550.h>
------------------------------------------------

This approach has disadvantage:
* the files mach/debug_ll_jz4740.h and mach/debug_ll_jz4755.h
(they go to arch/mips/arch-xburst) are __BOARD-SPECIFIC__
(not SOC- or mach-specific!); The file mach-xburst/include/mach/debug_ll.h
is outside board directory, but it contains some board related information.

This commit introduce a more suitable solution.

Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

arch/mips/boards/rzx50/include/board/debug_ll.h

@@ -18,12 +18,12 @@
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 
-#ifndef __INCLUDE_DEBUG_LL_JZ4755_H__
-#define __INCLUDE_DEBUG_LL_JZ4755_H__
+#ifndef __INCLUDE_RZX50_BOARD_DEBUG_LL_H__
+#define __INCLUDE_RZX50_BOARD_DEBUG_LL_H__
 
 #include <mach/jz4750d_regs.h>
 
 #define DEBUG_LL_UART_ADDR	UART1_BASE
 #define DEBUG_LL_UART_SHIFT	2
 
-#endif  /* __INCLUDE_DEBUG_LL_JZ4755_H__ */
+#endif  /* __INCLUDE_RZX50_BOARD_DEBUG_LL_H__ */

arch/mips/mach-xburst/include/mach/debug_ll.h

@@ -24,10 +24,7 @@
 /** @file
  *  This File contains declaration for early output support
  */
-#ifdef CONFIG_BOARD_RZX50
-#include <mach/debug_ll_jz4755.h>
-#endif
-
+#include <board/debug_ll.h>
 #include <debug_ll_ns16550.h>
 
 #endif  /* __MACH_XBURST_DEBUG_LL__ */