scsi: ufs: Remove two WB related fields from struct ufs_dev_info

scsi: ufs: Remove two WB related fields from struct ufs_dev_info

d_wb_alloc_units and d_ext_ufs_feature_sup are only used during WB probe.
They are used to confirm the condition that "if bWriteBoosterBufferType
is set to 01h but dNumSharedWriteBoosterBufferAllocUnits is set to zero,
the WriteBooster feature is disabled", and if UFS device supports WB.

No need to keep them after probing is complete.

Link: https://lore.kernel.org/r/20210119163847.20165-5-huobean@gmail.com
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>