This would help gtk-egl display showing scaled DMABuf cursor images when
gtk window was zoomed. A default scale of (1.0, 1.0) was presumed for
call sites where no scaling is needed.

Signed-off-by: Chen Zhang <tgfbeta@me.com>
Message-id: 23B229B3-3095-4DFB-8369-866784808D30@me.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>