mac80211: remove "bcn_int" and "capab" scan results info

These bits were dead code before "mac80211: Remove local->scan_flags"
(commit 6681dd3fd0e4d36a4547415853e83411baa7b705) and probably should
have been removed as part of that commit.

Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>