iwlwifi: mvm: reprobe device on firmware error during restart

If we get a firmware error during restart, we currently abandon any
hope and simply fail, getting stuck until the driver is reloaded.
Unfortunately, there isn't really much else we can do since restart
will likely continue to fail, and asking mac80211 for disconnection
just causes more error.

To allow the user to at least set up the device again completely
from scratch, reprobe the device and in doing so completely destroy
any mac80211/driver state.

Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>