update libvpx in EL6

[Kevin Kofler]

Ken Dreyer wrote:
> In order to have proper WebM/VP8 in ffmpeg, I filed
> https://bugzilla.redhat.com/755305 to request a libvpx update in RHEL
> 6. (I don't personally have a support contract with Red Hat, so I
> don't know how much weight this will have.)

Looks like none at all:
https://bugzilla.redhat.com/show_bug.cgi?id=755305#c2
:-(

        Kevin Kofler