pinctrl: add abx500 pinctrl driver core

This adds the AB8500 core driver, which will be utilized by
the follow-on drivers for different ABx500 variants.
Sselect the driver from the DBX500_SOC, as this chip is
powering and clocking that SoC.

Cc: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/arch/arm/mach-ux500/Kconfig b/arch/arm/mach-ux500/Kconfig
index 1d7dbe6..018bf68 100644
--- a/arch/arm/mach-ux500/Kconfig
+++ b/arch/arm/mach-ux500/Kconfig
@@ -11,6 +11,7 @@
 	select COMMON_CLK
 	select PINCTRL
 	select PINCTRL_NOMADIK
+	select PINCTRL_ABX500
 	select PL310_ERRATA_753970 if CACHE_PL310
 
 config UX500_SOC_DB8500