platform/x86: ideapad-laptop: send notification about touchpad state change to sysfs

Consumers can determine if the value of an attribute changed much more
easily if changes are broadcast using sysfs_notify(), so utilize it.
Signed-off-by: NBarnabás Pőcze <pobrn@protonmail.com>
Reviewed-by: NHans de Goede <hdegoede@redhat.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20210203215403.290792-26-pobrn@protonmail.comSigned-off-by: NHans de Goede <hdegoede@redhat.com>

drivers/platform/x86/ideapad-laptop.c

@@ -1221,6 +1221,7 @@ static void ideapad_sync_touchpad_state(struct ideapad_private *priv)
 		 */
 		i8042_command(&param, value ? I8042_CMD_AUX_ENABLE : I8042_CMD_AUX_DISABLE);
 		ideapad_input_report(priv, value ? 67 : 66);
+		sysfs_notify(&priv->platform_device->dev.kobj, NULL, "touchpad");
 	}
 }