scsi: ufs: core: Only call scsi_host_busy() after the SCSI host has been added

scsi: ufs: core: Only call scsi_host_busy() after the SCSI host has been added

scsi_host_busy() iterates over the host tag set. The host tag set is
initialized by scsi_mq_setup_tags(). The latter function is called by
scsi_add_host(). Hence only call scsi_host_busy() after the SCSI host
has been added. This patch prepares for reverting commit a0b7780602b1
("scsi: core: Fix a regression triggered by scsi_host_busy()").

Reviewed-by: John Garry <john.g.garry@oracle.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://patch.msgid.link/20260109205104.496478-2-bvanassche@acm.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>