ecore-wl2: Ensure display cleanup after roundtrips

ecore-wl2: Ensure display cleanup after roundtrips

Commit ee52a28d041dfb02da0f2deca0714beb5eaa51fd added a roundtrip to
ensure and pending wl events were handled before we disconnected the
display. While this ensures some things like session recovery destroy
work again, it lead to an issue where the _ecore_wl2_display_cleanup
function was called BEFORE we processed pending events. This (in turn)
causes crashes due to processing of pending events that relied on
things like Ecore_Wl2_Input existing. As the display cleanup function
clears inputs & outputs, we need to defer calling that until the
display_roundtrip has dispatched and handled pending events.

@fix

Signed-off-by: Chris Michael <cp.michael@samsung.com>