mesa-dri-swrast no longer exists and just installs,
mesa-dri-gallium. However, this might not always be the case, so
let's change it before it causes any issues.
[ci:ignore-count]
[ci:skip-build]
[ci:ignore-count]
[ci:skip-vercheck] needed for the postmarketos-ui-* packages in this
series
[ci:skip-build] already built ui-* packages in CI, and device pacakges
are just trivial deviceinfo change (manually built some just to verify)