radv: Only emit what is appropriate to the queue family for preambles.

radv: Only emit what is appropriate to the queue family for preambles.

This makes the function easier to read and follow.
Also prepares for some future changes when we'll want to
submit to multiple queues at once.

Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Reviewed-By: Tatsuyuki Ishi <ishitatsuyuki@gmail.com>
Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/16358>