unicore32: default GENERIC_GPIO to false

GPIO implementation for unicore32 uses gpiolib, which sets GENERIC_GPIO
when selected.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>

arch/unicore32/Kconfig

@@ -24,7 +24,7 @@ config UNICORE32
 	  Please see web page at <http://www.pkunity.com/>.
 
 config GENERIC_GPIO
-	def_bool y
+	bool
 
 config GENERIC_CSUM
 	def_bool y