gpio: do not include <asm/arch/gpio.h> for UniPhier

I implemented a GPIO driver based on Driver Model for the UniPhier
SoC family, but I could not find any good reason why such SoC
specific GPIO headers are needed.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/include/asm/gpio.h b/arch/arm/include/asm/gpio.h
index d49ad08..fe4419c 100644
--- a/arch/arm/include/asm/gpio.h
+++ b/arch/arm/include/asm/gpio.h
@@ -1,2 +1,4 @@
+#ifndef CONFIG_ARCH_UNIPHIER
 #include <asm/arch/gpio.h>
+#endif
 #include <asm-generic/gpio.h>