Fix DPMS handling regressions

This patch fixes two separate regressions. The first one was introduced
in 3d04f9e, where the `sleeping` field was renamed to `display_on`.
Since the field's value was inverted, it was necessary to switch all
conditionals accessing this field, which was forgotten for the one that
toggles the accelerometer timer on DPMS on/off.

Then 64279b2 made use of the same conditional to simulate activity
whenever the display is turned on, however it accidentally checked for
the display to be off. As a result turning the display off would
automatically cause activity, waking the display back up.

src/catacomb.rs

@@ -447,15 +447,15 @@ impl Catacomb {
 
         // Pause accelerometer checks while display is off.
         if on {
-            trace_error!(self.event_loop.disable(&self.accelerometer_token));
-        } else if !self.windows.orientation_locked() {
-            trace_error!(self.event_loop.enable(&self.accelerometer_token));
-        }
-
-        // Count wakeup as activity, to ensure that clients like wayidle receive a
-        // resume and new idle events after waking the monitor back up.
-        if !on {
+            // Count wakeup as activity, to ensure that clients like wayidle receive a
+            // resume and new idle events after waking the monitor back up.
             self.idle_notifier_state.notify_activity(&self.seat);
+
+            if !self.windows.orientation_locked() {
+                trace_error!(self.event_loop.enable(&self.accelerometer_token));
+            }
+        } else {
+            trace_error!(self.event_loop.disable(&self.accelerometer_token));
         }
 
         self.backend.set_display_status(on);

src/input.rs

@@ -449,7 +449,6 @@ impl Catacomb {
                                     self.touch_state.last_tap =
                                         Some((Instant::now(), event.position));
                                 },
-                                // TODO: Update idle timeout.
                                 Some(TouchAction::DoubleTap) => self.set_display_status(true),
                                 _ => (),
                             }