ufs: flush dcache before reading transfer result

Sometimes we get a cache hit and read back the default OCS value (0xf)
in ufs_scsi_exec(). Add a flush_dcache_range() call to prevent this.

Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>
diff --git a/drivers/ufs/ufs.c b/drivers/ufs/ufs.c
index 05befc0..da55eb0 100644
--- a/drivers/ufs/ufs.c
+++ b/drivers/ufs/ufs.c
@@ -1583,6 +1583,8 @@
 
 	ufshcd_send_command(hba, TASK_TAG);
 
+	flush_dcache_range((unsigned long)hba->utrdl, sizeof(struct utp_transfer_req_desc));
+
 	ocs = ufshcd_get_tr_ocs(hba);
 	switch (ocs) {
 	case OCS_SUCCESS: