pinctrl: capri: add dependency on OF

As this driver is using pinconf_generic_dt_node_to_map_pin() it
needs to depend on OF so as not to cause build problems on
archs that do not support OF.

Cc: Sherman Yin <syin@broadcom.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
index f1dda4d..be361b7 100644
--- a/drivers/pinctrl/Kconfig
+++ b/drivers/pinctrl/Kconfig
@@ -106,6 +106,7 @@
 
 config PINCTRL_CAPRI
 	bool "Broadcom Capri pinctrl driver"
+	depends on OF
 	select PINMUX
 	select PINCONF
 	select GENERIC_PINCONF