ARM: OMAP: move debug_card_init() function

debug_card_init() function resides in the plat/board.h file.
Move it to a separate header file under plat/ so the board.h file can be
removed.

Signed-off-by: Igor Grinberg <grinberg@compulab.co.il>
Signed-off-by: Tony Lindgren <tony@atomide.com>
diff --git a/arch/arm/mach-omap2/board-h4.c b/arch/arm/mach-omap2/board-h4.c
index ace2048..5be30e6 100644
--- a/arch/arm/mach-omap2/board-h4.c
+++ b/arch/arm/mach-omap2/board-h4.c
@@ -32,11 +32,11 @@
 #include <asm/mach/arch.h>
 #include <asm/mach/map.h>
 
-#include <plat/board.h>
 #include "common.h"
 #include <plat/menelaus.h>
 #include <plat/dma.h>
 #include <plat/gpmc.h>
+#include <plat/debug-devices.h>
 
 #include <video/omapdss.h>
 #include <video/omap-panel-generic-dpi.h>