When deleting an interface in firmware-signalling module it will
clear any destination descriptors. To avoid concurrency issues it
should take the lock using brcmf_fws_lock().
Reviewed-by: NHante Meuleman <meuleman@broadcom.com>
Reviewed-by: NPieter-Paul Giesberts <pieterpg@broadcom.com>
Signed-off-by: NArend van Spriel <arend@broadcom.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>