rt2x00: change beaconing locking

This patch is needed for further changes to keep global variables
consistent when changing beaconing on diffrent vif's.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --cc drivers/net/wireless/rt2x00/rt2x00dev.c
Simple merge

diff --cc drivers/net/wireless/rt2x00/rt2x00mac.c
Simple merge

diff --cc drivers/net/wireless/rt2x00/rt2x00queue.c
Simple merge