Fix setting appsrc properties in i686 arch
Fix setting appsrc properties in i686 arch

The "max-bytes" property of the appsrc GStreamer element expects a
64-bit value. Calling:
g_object_set(source, "max-bytes", 0, NULL);
in a 32-bit architecture ends up with a wrong value, it must be cast to
a gint64:
g_object_set(source, "max-bytes", G_GINT64_CONSTANT(0), NULL);

Acked-by: Frediano Ziglio <55d48b080b2e443e395cde84d2c83b135a4ff48e@redhat.com>

flexVDI/spice-gtk,flexVDI/spice-gtk