brcmfmac: use struct brcmf_if parameter in firmware event callbacks

Firmware events are passed to wl_cfg80211 module associated with
the primary net device. With virtual interface support events can
be received for different interfaces, ie. struct brcmf_if instances.
Pass it in the event to determine appropriate net device associated
with the event.

Reviewed-by: Hante Meuleman <meuleman@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Franky Lin <frankyl@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>