cxgb4: Inform caller if driver didn't upgrade firmware

If a card had already been initialized, on reloading cxgb4 driver firmware
required an upgrade but the upgrade did not happen. In that case a mailbox
timeout would occur during T4 configuration file stuff. The fix is to let the
caller know the firmware was not upgraded so a reset would be issued before
starting the T4 config stuff.

Signed-off-by: Jay Hernandez <jay@chelsio.com>
Signed-off-by: Vipul Pandya <vipul@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>