scsi: sd: Print write through due to no caching mode page as warning

For SD cardreaders it is extremely common not to have a cache.
Consequently, the following messages do not point to a real error one could
try to fix but rather describe how the disk works:

  sd 0:0:0:0: [sda] No Caching mode page found
  sd 0:0:0:0: [sda] Assuming drive cache: write through

Print these messages as warnings instead of errors.

Link: https://lore.kernel.org/r/20211013075050.3870354-1-martin.kepplinger@puri.smReviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/sd.c

@@ -2792,7 +2792,8 @@ sd_read_cache_type(struct scsi_disk *sdkp, unsigned char *buffer)
 			}
 		}
 
-		sd_first_printk(KERN_ERR, sdkp, "No Caching mode page found\n");
+		sd_first_printk(KERN_WARNING, sdkp,
+				"No Caching mode page found\n");
 		goto defaults;
 
 	Page_found:
@@ -2847,7 +2848,7 @@ sd_read_cache_type(struct scsi_disk *sdkp, unsigned char *buffer)
 				"Assuming drive cache: write back\n");
 		sdkp->WCE = 1;
 	} else {
-		sd_first_printk(KERN_ERR, sdkp,
+		sd_first_printk(KERN_WARNING, sdkp,
 				"Assuming drive cache: write through\n");
 		sdkp->WCE = 0;
 	}