at76c50x-usb: add driver

This is a driver for usb devices based on at76c50x chipset. This is
a mac80211 port of the original at76_usb driver.

Signed-off-by: Kalle Valo <kalle.valo@iki.fi>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/Makefile b/drivers/net/wireless/Makefile
index ac590e1c..e2574ca 100644
--- a/drivers/net/wireless/Makefile
+++ b/drivers/net/wireless/Makefile
@@ -24,6 +24,8 @@
 obj-$(CONFIG_PCI_ATMEL)         += atmel_pci.o 
 obj-$(CONFIG_PCMCIA_ATMEL)      += atmel_cs.o
 
+obj-$(CONFIG_AT76C50X_USB)      += at76c50x-usb.o
+
 obj-$(CONFIG_PRISM54)		+= prism54/
 
 obj-$(CONFIG_HOSTAP)		+= hostap/