rmobile: Drop CONFIG_SH73A0 and associated code

This option does not exist, so the code attached to it is not used. Drop
it.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/mach-rmobile/include/mach/gpio.h b/arch/arm/mach-rmobile/include/mach/gpio.h
index 6b5e4ed..150aa46 100644
--- a/arch/arm/mach-rmobile/include/mach/gpio.h
+++ b/arch/arm/mach-rmobile/include/mach/gpio.h
@@ -1,10 +1,7 @@
 #ifndef __ASM_ARCH_GPIO_H
 #define __ASM_ARCH_GPIO_H
 
-#if defined(CONFIG_SH73A0)
-#include "sh73a0-gpio.h"
-void sh73a0_pinmux_init(void);
-#elif defined(CONFIG_R8A7740)
+#if defined(CONFIG_R8A7740)
 #include "r8a7740-gpio.h"
 void r8a7740_pinmux_init(void);
 #endif