Delete ufshcd_read_desc(). Instead, let caller directly call
ufshcd_read_desc_param().

Link: https://lore.kernel.org/r/20200603091959.27618-3-huobean@gmail.comReviewed-by: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Bart van Assche <bvanassche@acm.org>
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>