iommu/omap: Protect omap-iopgtable.h against double inclusion

Protect the omap-pgtable.h header against double inclusion in
source code by using the standard include guard mechanism.
Signed-off-by: Suman Anna <s-anna@ti.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/omap-iopgtable.h

@@ -10,6 +10,9 @@
  * published by the Free Software Foundation.
  */
 
+#ifndef _OMAP_IOPGTABLE_H
+#define _OMAP_IOPGTABLE_H
+
 /*
  * "L2 table" address mask and size definitions.
  */
@@ -93,3 +96,5 @@ static inline phys_addr_t omap_iommu_translate(u32 d, u32 va, u32 mask)
 /* to find an entry in the second-level page table. */
 #define iopte_index(da)		(((da) >> IOPTE_SHIFT) & (PTRS_PER_IOPTE - 1))
 #define iopte_offset(iopgd, da)	(iopgd_page_vaddr(iopgd) + iopte_index(da))
+
+#endif /* _OMAP_IOPGTABLE_H */