SoC: exynos: add support for exynos 78x0

Samsung Exynos 7880 \ 7870 - SoC for mainstream smartphones and tablets
introduced on March 2017.
Features:
- 8 Cortex A53 cores
- ARM Mali-T830 MP3 GPU
- LTE Cat. 7 (7880) or 6 (7870) modem

Signed-off-by: Dzmitry Sankouski <dsankouski@gmail.com>
Cc: Minkyu Kang <mk7.kang@samsung.com>
diff --git a/drivers/pinctrl/exynos/Kconfig b/drivers/pinctrl/exynos/Kconfig
index 84b6aaa..a60f498 100644
--- a/drivers/pinctrl/exynos/Kconfig
+++ b/drivers/pinctrl/exynos/Kconfig
@@ -8,3 +8,11 @@
 	help
 	  Support pin multiplexing and pin configuration control on
 	  Samsung's Exynos7420 SoC.
+
+config PINCTRL_EXYNOS78x0
+	bool "Samsung Exynos78x0 pinctrl driver"
+	depends on ARCH_EXYNOS && PINCTRL_FULL
+	select PINCTRL_EXYNOS
+	help
+	  Support pin multiplexing and pin configuration control on
+	  Samsung's Exynos78x0 SoC.