minstrel: make the rate control ops reusable from another rc implementation

This patch makes it possible to reuse the minstrel rate control ops
from another rate control module. This is useful in preparing for the
new 802.11n implementation of minstrel, which will reuse the old code
for legacy stations.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/rc80211_minstrel.c b/net/mac80211/rc80211_minstrel.c
index 6e5d68b..4926d92 100644
--- a/net/mac80211/rc80211_minstrel.c
+++ b/net/mac80211/rc80211_minstrel.c
@@ -541,7 +541,7 @@
 	kfree(priv);
 }
 
-static struct rate_control_ops mac80211_minstrel = {
+struct rate_control_ops mac80211_minstrel = {
 	.name = "minstrel",
 	.tx_status = minstrel_tx_status,
 	.get_rate = minstrel_get_rate,