[SCSI] bfa: dereferencing freed memory in bfad_im_probe()

If bfad_thread_workq(bfad) was not BFA_STATUS_OK then we freed "im"
and then dereferenced it.

I did a little clean up because it seemed nicer to return directly
instead of doing a superfluous goto.  I looked at other functions in
this file and it seems like returning directly is standard.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Krishna Gudipati <kgudipat@brocade.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>