asm/omap_gpmc.h: consolidate common defines

arch/arm/include/asm/arch-am33xx/omap_gpmc.h and
arch/arm/include/asm/arch-omap3/omap_gpmc.h are almost the same, consolidate
the common parts into a new header.

Introduce a new asm/omap_gpmc.h which defines the command part and pulls in
the architecture specific one.

Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com>
Cc: Tom Rini <trini@ti.com>
Reviewed-by: Tom Rini <trini@ti.com>
diff --git a/arch/arm/cpu/armv7/am33xx/elm.c b/arch/arm/cpu/armv7/am33xx/elm.c
index 9eed23d..41df612 100644
--- a/arch/arm/cpu/armv7/am33xx/elm.c
+++ b/arch/arm/cpu/armv7/am33xx/elm.c
@@ -33,7 +33,7 @@
 #include <asm/io.h>
 #include <asm/errno.h>
 #include <asm/arch/cpu.h>
-#include <asm/arch/omap_gpmc.h>
+#include <asm/omap_gpmc.h>
 #include <asm/arch/elm.h>
 
 #define ELM_DEFAULT_POLY (0)