exynos: fix header inclusion guard

It seems like the header inclusion guard for the Exynos pinctrl header
was misspelled.

Make the preprocessor symbol for the #ifndef and #define lines the
same, so that the double inclusion protection works as expected.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/drivers/pinctrl/exynos/pinctrl-exynos.h b/drivers/pinctrl/exynos/pinctrl-exynos.h
index a7788b7..cbc5174 100644
--- a/drivers/pinctrl/exynos/pinctrl-exynos.h
+++ b/drivers/pinctrl/exynos/pinctrl-exynos.h
@@ -6,7 +6,7 @@
  */
 
 #ifndef __PINCTRL_EXYNOS_H_
-#define __PINCTRL_EXYNOS__H_
+#define __PINCTRL_EXYNOS_H_
 
 #define PIN_CON		0x00	/* Offset of pin function register */
 #define PIN_DAT		0x04	/* Offset of pin data register */