Currently, the UFS driver busy waits for fDeviceInit to be cleared. Provide
an upper bound and sleep between attempts instead of busy waiting.

Link: https://lore.kernel.org/r/1597053747-75171-1-git-send-email-kwmad.kim@samsung.comTested-by: Kiwoong Kim <kwmad.kim@samsung.com>
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Kiwoong Kim <kwmad.kim@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>