brcmfmac: add additional parameter to brcmf_free_vif()

Pass the struct brcmf_cfg80211_info instance instead of obtaining
through vif itself using vif->wdev. This is needed as the netdev
associated with this vif is already unregistered.

Reviewed-by: Hante Meuleman <meuleman@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>