mac80211: clean up rate control code

It seems exceedingly unlikely that we'll ever
support swapping rate control algorithms at
runtime, so remove the unused refcounting code.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --cc net/mac80211/rate.c
Simple merge

diff --cc net/mac80211/rate.h
Simple merge

diff --cc net/mac80211/sta_info.c
Simple merge