rusticl: add freedreno alias for RUSTICL_ENABLE
What does this MR do and why?
rusticl: add freedreno alias for RUSTICL_ENABLE
`RUSTICL_ENABLE=msm` isn't first thought usually,
let's support the `freedreno` alias.
Suggested-by: Karol Herbst <kherbst@redhat.com>
Signed-off-by: David Heidelberg <david.heidelberg@collabora.com>