iommu/exynos: Remove excessive includes and sort others alphabetically

Removed following unused includes: <linux/mm.h>, <linux/errno.h>,
<linux/memblock.h> and <linux/export.h>.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/exynos-iommu.c

@@ -12,19 +12,15 @@
 #define DEBUG
 #endif
 
-#include <linux/io.h>
-#include <linux/interrupt.h>
-#include <linux/platform_device.h>
-#include <linux/slab.h>
-#include <linux/pm_runtime.h>
 #include <linux/clk.h>
 #include <linux/err.h>
-#include <linux/mm.h>
+#include <linux/io.h>
 #include <linux/iommu.h>
-#include <linux/errno.h>
+#include <linux/interrupt.h>
 #include <linux/list.h>
-#include <linux/memblock.h>
-#include <linux/export.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
 
 #include <asm/cacheflush.h>
 #include <asm/pgtable.h>