drm/exynos: fix build warnings from ipp fimc

Becuase of order of headers, there are build warnings and they are
fixed with this patch.

Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

drivers/gpu/drm/exynos/exynos_drm_fimc.c

@@ -12,9 +12,9 @@
  *
  */
 #include <linux/kernel.h>
-#include <linux/mfd/syscon.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
+#include <linux/mfd/syscon.h>
 #include <linux/regmap.h>
 #include <linux/clk.h>
 #include <linux/pm_runtime.h>