rts8891: fix format string

backend/rts8891.c

@@ -3776,8 +3776,8 @@ init_device (struct Rts8891_Device *dev)
       sprintf (message, "init_device: initial register settings: ");
       for (i = 0; i < dev->reg_count; i++)
 	sprintf (message + strlen (message), "0x%02x ", dev->regs[i]);
-      sprintf (message + strlen (message), "\n");
-      DBG (DBG_io2, message);
+
+      DBG (DBG_io2, "%s\n", message);
     }
 
   /* initial sensor guess */