dell-wmi: don't generate errors on empty messages

There's no point in generating kernel messages if we didn't receive a
parsable keyboard event - only do so if there appeared to be a scancode.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>

drivers/platform/x86/dell-wmi.c

@@ -176,9 +176,9 @@ static void dell_wmi_notify(u32 value, void *context)
 			input_sync(dell_wmi_input_dev);
 			input_report_key(dell_wmi_input_dev, key->keycode, 0);
 			input_sync(dell_wmi_input_dev);
-		} else
+		} else if (buffer[1] & 0xFFFF)
 			printk(KERN_INFO "dell-wmi: Unknown key %x pressed\n",
-			       buffer[1]);
+			       buffer[1] & 0xFFFF);
 	}
 }