Revert "wayland-surface: Apply the surface scale only if needed"

This commit is wrong, it assumes that the scale only applies to the one
set by the client but its not. meta_surface_actor_wayland_scale_texture
also handles the output scale. Revert the commit to fix hidpi for wayland
clients like weston-terminal.

This reverts commit 0364ea91.

https://bugzilla.gnome.org/show_bug.cgi?id=739161