gpio: xtensa: depend on HAVE_XTENSA_GPIO32

Prevent build failure when the selected variant does not support GPIO32.

Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 1a07c40..858d489 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -300,6 +300,7 @@
 config GPIO_XTENSA
 	bool "Xtensa GPIO32 support"
 	depends on XTENSA
+	depends on HAVE_XTENSA_GPIO32
 	depends on !SMP
 	help
 	  Say yes here to support the Xtensa internal GPIO32 IMPWIRE (input)