scsi: ufs: export ufshcd_link_recovery

Export ufshcd_link_recovery to allow vendors to recover failed link in
vendor's callbacks.

Link: https://lore.kernel.org/r/20200327095329.10083-2-stanley.chu@mediatek.com


Reviewed-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>