MIPS: BCM47XX: Get GPIO pin from nvram configuration

The nvram contains some gpio configuration for boards. It is stored in
a gpio<number>=name format e.g.
gpio8=wps_button
gpio4=robo_reset

This patches adds a function to parse these entries, so other driver
can use it.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5841/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/include/asm/mach-bcm47xx/bcm47xx_nvram.h b/arch/mips/include/asm/mach-bcm47xx/bcm47xx_nvram.h
index b8e7be8..36a3fc1 100644
--- a/arch/mips/include/asm/mach-bcm47xx/bcm47xx_nvram.h
+++ b/arch/mips/include/asm/mach-bcm47xx/bcm47xx_nvram.h
@@ -48,4 +48,6 @@
 		printk(KERN_WARNING "Can not parse mac address: %s\n", buf);
 }
 
+int bcm47xx_nvram_gpio_pin(const char *name);
+
 #endif /* __BCM47XX_NVRAM_H */