Enables video support in ardour by default.
I do a lot of sound design using ardour and in turn have it enabled in
my configuration. However, seeing as hydra only builds the default
configuration, the build I need is never cached, and I always end up
needing to build ardour from scratch which takes over an hour on my
small laptop. The `videoSupport` flag itself just ensures that xjadeo
and harvid (both required for video support to work in ardour) are
accessible via the PATH.
30e9e7bea5