A non-zero error value likely being returned by ufshcd_scsi_add_wlus() in
case of failure of adding the WLs, but ufshcd_probe_hba() doesn't use this
value, and doesn't report this failure to upper caller.  This patch is to
fix this issue.

Fixes: 2a8fa600 ("ufs: manually add well known logical units")
Link: https://lore.kernel.org/r/20200120130820.1737-2-huobean@gmail.comReviewed-by: Asutosh Das <asutoshd@codeaurora.org>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>