nl80211: allow sending CMD_FRAME without specifying any frequency
nl80211: allow sending CMD_FRAME without specifying any frequency

Users may want to send a frame on the current channel
without specifying it.

This is particularly useful for the correct implementation
of the IBSS/RSN support in wpa_supplicant which requires to
receive and send AUTH frames.

Make mgmt_tx pass a NULL channel to the driver if none has
been specified by the user.

Signed-off-by: Antonio Quartulli <a08f08bac39aeae6c9580ade7aa8387b5a0e7428@open-mesh.com>
Signed-off-by: Johannes Berg <bff32994ff0f8d048f262a8388145a71b6071bfe@intel.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs