cxgb4: Fix error handling path in 'init_one()'

Commit baf50868 ("cxgb4: restructure VF mgmt code") has reordered
some code but an error handling label has not been updated accordingly.
So fix it and free 'adapter' if 't4_wait_dev_ready()' fails.

Fixes: baf50868 ("cxgb4: restructure VF mgmt code")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>