pinctrl: uniphier: add COMPILE_TEST option

Add COMPILE_TEST for the compilation test coverage.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/uniphier/Kconfig

 menuconfig PINCTRL_UNIPHIER
 	bool "UniPhier SoC pinctrl drivers"
-	depends on ARCH_UNIPHIER
+	depends on ARCH_UNIPHIER || COMPILE_TEST
 	depends on OF && MFD_SYSCON
 	default y
 	select PINMUX