SMB3: Log at least once if tree connect fails during reconnect

Adding an extra debug message to show if a tree connect failure during
reconnect (and made it a log once so it doesn't spam the logs).
Saw a case recently where tree connect repeatedly returned
access denied on reconnect and it wasn't as easy to spot as it
should have been.

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>