iwlegacy: fix sparse warnings

Make local functions and tables static. Make ops table
Mark 3945 ops as read_mostly.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/iwlegacy/3945-mac.c b/drivers/net/wireless/iwlegacy/3945-mac.c
index 3630a41..df5a57c 100644
--- a/drivers/net/wireless/iwlegacy/3945-mac.c
+++ b/drivers/net/wireless/iwlegacy/3945-mac.c
@@ -3475,7 +3475,7 @@
 	.attrs = il3945_sysfs_entries,
 };
 
-struct ieee80211_ops il3945_mac_ops = {
+static struct ieee80211_ops il3945_mac_ops __read_mostly = {
 	.tx = il3945_mac_tx,
 	.start = il3945_mac_start,
 	.stop = il3945_mac_stop,