Use GDK_VERSION_MAX_ALLOWED
Use GDK_VERSION_MAX_ALLOWED

In order to avoid using a too new Gtk API.

Taken from virt-viewer 4c4a43c61db60ac815c0bc66730fa0a9a1571103

Acked-by: Eduardo Lima (Etrunko) <025eb0974a9f48eaca88b86d8c2bcaf361e95a91@redhat.com>

SPICE/spice-gtk,SPICE/spice-gtk,flexVDI/spice-gtk,fgouget/spice-gtk,fgouget/spice-gtk,SPICE/spice-gtk,SPICE/spice-gtk,fgouget/spice-gtk,flexVDI/spice-gtk