There is an updated pull request by gbrlsnchs against master on the void-packages repository

https://github.com/gbrlsnchs/void-packages fix-fzf-nvim
https://github.com/void-linux/void-packages/pull/21733

fzf: install fzf.vim to Neovim plugin directory
For Vim users, FZF works out of the box, but Neovim users have to
manually copy /usr/share/vim/vimfiles/plugin/fzf.vim to the proper
Neovim equivalent.

A patch file from https://github.com/void-linux/void-packages/pull/21733.patch is attached