sfc: call mcdi_reboot_detected() when MC reboots during an MCDI command

This function wasn't being called in this particular case when the MC
 reboots. This caused resource reallocations to not be handled properly
 and often ended up disabling the interface.

Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>