staging: wfx: fix potential dead lock between join and scan

staging: wfx: fix potential dead lock between join and scan

The device disallows to start a scan request between hif_join() and
hif_set_bss_params(). The driver is not protected against that. The
worst case happens when association is aborted and hif_set_bss_params()
never happens.

mac80211 would never ask for scan during the association process. So,
this patch just aborts the association in progress when scan is
requested.

Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Link: https://lore.kernel.org/r/20200515083325.378539-14-Jerome.Pouiller@silabs.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>