va: caps: Add image formats in raw caps only for non-iHD.

va: caps: Add image formats in raw caps only for non-iHD.

This plugin, for decoders more concretely, assumes that a VA config
can do certain color conversions when mapping frames onto CPU's
memory.

This assumption was valid for i965 and Gallium drivers which generates
valid outputs in bitstreams testers (v.gr. fluster). Nonetheless, iHD,
even when it generates acceptable rendered frames, output's MD5 of
tests weren't valid.

This patch append the image formats, for color conversion when mapping
to memory, for non-iHD drivers.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/2128>