brcmfmac: add a function designated for handling firmware fails

This improves handling PCIe firmware halts by printing a clear error
message and replaces a similar code in the SDIO bus support.

It will also allow further improvements like trying to recover from a
firmware crash.

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