This is a continuation of a patch series adding 9p server support for Darwin,
originally submitted by Keno Fischer in mid-2018
(https://lists.gnu.org/archive/html/qemu-devel/2018-06/msg04643.html).

It has since been updated and rebased for NixOS by Michael Roitzsch
(https://github.com/NixOS/nixpkgs/pull/122420) with a goal of resubmitting
upstream. I am submitting his patch set as suggested, as developed by him, with
his Signed-off-by headers included in full.

Additionally, I have run the patches through checkpatch.pl and adjusted coding
style accordingly (with the exception of ignoring warnings about avoid
architecture specific defines in hw/9pfs/9p-util-darwin.c, where they seem
unavoidable), and have signed off on those modified commits.