nvme-loop: don't put ctrl on nvme_init_ctrl error

The function nvme_init_ctrl() gets the ctrl reference & when it fails it
does put the ctrl reference in the error unwind code.

When creating loop ctrl in nvme_loop_create_ctrl() if nvme_init_ctrl()
returns non zero (i.e. error) value it jumps to the "out_put_ctrl" label
which calls nvme_put_ctrl(), that will lead to douple ctrl put in error
unwind path.

Update nvme_loop_create_ctrl() such that this patch removes the
"out_put_ctrl" label, add a new "out" label after nvme_put_ctrl() in
error unwind path and jump to newly added label when nvme_init_ctrl()
call retuns an error.

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>