[PATCH] bcm43xx: remove dead statistics code

This patch removes code that was make obsolete when the wireless
statistics in bcm43xx-softmac were changed, but was overlooked at that
time. The value of bcm->stats.link_quality computed here is never used.

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>