Add GPIO bus to config and hints. Also add sample gpioled device.

sys/mips/conf/AR71XX

@@ -74,6 +74,9 @@ options		USB_EHCI_BIG_ENDIAN_DESC        # handle big-endian byte order
 device		ohci
 device		ehci
 
+device		gpio
+device		gpioled
+
 device		spibus
 device		ar71xx_spi
 device		mx25l

sys/mips/conf/AR71XX.hints

@@ -47,6 +47,18 @@ hint.arge.1.fduplex=1
 # Uncomment this hint for RS (not PRO)
 # hint.arge.0.phymask=70000
 
+# GPIO
+hint.gpio.0.at="apb0"
+hint.gpio.0.maddr=0x18040000
+hint.gpio.0.msize=0x1000
+hint.gpio.0.irq=2
+
+# RF led
+hint.gpioled.0.at="gpiobus0"
+hint.gpioled.0.name="rf"
+# pin 2
+hint.gpioled.0.pins=0x0004
+
 # SPI flash
 hint.spi.0.at="nexus0"
 hint.spi.0.maddr=0x1f000000