[SCSI] ufshcd-pltfrm: add missing empty slot in ufs_of_match[]

of_match_table member in struct device_driver must be terminated by
empty slot as a sentinel.

Signed-off-by: Akinobu Mita <mita@fixstars.com>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>