[WIRELESS]: Fix config dependencies.

I accidentally ended up with a config that set NET_RADIO off,
and NET_WIRELESS_RTNETLINK on, which blew up thus..

net/built-in.o: In function `do_setlink':net/core/rtnetlink.c:479: undefined reference to `wireless_rtnetlink_set'
net/built-in.o: In function `do_getlink':net/core/rtnetlink.c:521: undefined reference to `wireless_rtnetlink_get'

Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/wireless/Kconfig b/drivers/net/wireless/Kconfig
index 6a1033e..fd17aa8 100644
--- a/drivers/net/wireless/Kconfig
+++ b/drivers/net/wireless/Kconfig
@@ -27,6 +27,7 @@
 
 config NET_WIRELESS_RTNETLINK
 	bool "Wireless Extension API over RtNetlink"
+	depends on NET_RADIO
 	---help---
 	  Support the Wireless Extension API over the RtNetlink socket
 	  in addition to the traditional ioctl interface (selected above).