scsi: ufs: Remove unnecessary NULL checks in ufshcd_find_max_sup_active_icc_level()

vcc/vccq/vccq2 have already been NULL checked at this point in
ufshcd_find_max_sup_active_icc_level().

Link: https://lore.kernel.org/r/20210319070916.2254-1-zbestahu@gmail.com


Signed-off-by: Yue Hu <huyue2@yulong.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>