docked-manager: make tablets dockable too

The current code considers that only phones are dockable. This patch
improves the device mode check so that tablets also benefit from auto
mode switch (tested on the PineTab).

src/docked-manager.c

@@ -121,7 +121,8 @@ mode_changed_cb (PhoshDockedManager *self, GParamSpec *pspec, PhoshModeManager *
    * Desktops, laptops and phones with enough external hardware should get floating
    * windows, etc
    */
-  if (phosh_mode_manager_get_mimicry (manager) != PHOSH_MODE_DEVICE_TYPE_PHONE)
+  if (phosh_mode_manager_get_mimicry (manager) != PHOSH_MODE_DEVICE_TYPE_PHONE &&
+      phosh_mode_manager_get_mimicry (manager) != PHOSH_MODE_DEVICE_TYPE_TABLET)
     can_dock = TRUE;
 
   if (can_dock == self->can_dock)