cfg80211: Allow a scan request for a specific BSSID

This allows scans for a specific BSSID to be optimized by the user space
application by requesting the driver to set the Probe Request frame
BSSID field (Address 3) to the specified BSSID instead of the wildcard
BSSID. This prevents other APs from replying which reduces airtime need
and latency in getting the response from the target AP through.

This is an optimization and as such, it is acceptable for some of the
drivers not to support the mechanism. If not supported, the wildcard
BSSID will be used and more responses may be received.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Git-commit: 0889675a9503f48d1ad01b4eaa202f89469b2b62
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git


Change-Id: I20cf654661c11880055d022e0c9ec77beab659e8
CRs-fixed: 996660
Signed-off-by: Vidyullatha Kanchanapally <vidyullatha@codeaurora.org>