Waybar: update to 0.9.8.

[ifreund]

General

• This is a new package and it conforms to the quality requirements

Have the results of the proposed changes been tested?

• I use the packages affected by the proposed changes on a regular basis and confirm this PR works for me
• I generally don't use the affected packages but briefly tested this PR

cc @ericonr. I needed libxkbregistry in order to build master waybar so I thought I'd go ahead and bump the void package as well. Looks like the patch for fmt 8.0.0 has been upstreamed which is nice :)

[ericonr]

Neat

#32572 was doing a split for a sub package, what do you think?

[ifreund]

#32572 was doing a split for a sub package, what do you think?

Oh, I totally missed that PR. Since waybar seems to be the only think that needs libxkbregistry, splitting into a subpackage makes sense to me, just a minute.