ARM: OMAP: Make plat/omap_hwmod.h local to mach-omap2

Let's make omap_hwmod local to mach-omap2 for
ARM common zImage support.

Signed-off-by: Tony Lindgren <tony@atomide.com>
diff --git a/arch/arm/mach-omap2/drm.c b/arch/arm/mach-omap2/drm.c
index 67991ea..6282cc8 100644
--- a/arch/arm/mach-omap2/drm.c
+++ b/arch/arm/mach-omap2/drm.c
@@ -25,7 +25,7 @@
 #include <linux/dma-mapping.h>
 
 #include "omap_device.h"
-#include <plat/omap_hwmod.h>
+#include "omap_hwmod.h"
 
 #if defined(CONFIG_DRM_OMAP) || (CONFIG_DRM_OMAP_MODULE)