brcmfmac: destination mac closed when interface is closed

Firmware signals a destination is closed as well as an interface. A
destination is associated with an interface. When an interface is
closed consequently the destination should be considered closed as
well.

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: John W. Linville <linville@tuxdriver.com>