disk: part: Print out the unknown device uclass id

It's helpful to output the device uclass id for unknown devices
during the debugging process.

Signed-off-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Simon Glass <sjg@chromium.org>

disk/part.c

@@ -337,7 +337,7 @@ static void print_part_header(const char *type, struct blk_desc *desc)
 		puts("EFI");
 		break;
 	default:
-		puts("UNKNOWN");
+		printf("UNKNOWN(%d)", desc->uclass_id);
 		break;
 	}
 	printf (" device %d  --   Partition Type: %s\n\n",