brcmfmac: be more verbose when PSM's watchdog fires

It's important to inform user so he knows things went wrong. He may also
want to get memory dump for further debugging purposes.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Acked-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>