scsi: ufs: disable interrupt during clock-gating

Similar to suspend, ufshcd interrupt can be disabled since there won't be
any host controller transaction expected till clocks ungated.

Link: https://lore.kernel.org/r/1575721321-8071-3-git-send-email-stanley.chu@mediatek.com


Reviewed-by: Asutosh Das <asutoshd@codeaurora.org>
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>