`make install` fails on documentation when using Sphinx 4

Hello,

Installing qemu from git (and tag v6.0.0) fails during make install. The cause of the issue appears to be a discrepancy between the paths in a makefile (build/Makefile.ninja?) and the actual path in the build/ directory.

In particular, the file is listed as docs/qemu-qmp-ref.7, but its location is docs/7/qemu-qmp-ref.7. This error may occur with other doc files; I haven't noticed it as Meson raises an exception (using Python 3.8):

Traceback (most recent call last):
  File "/home/kbjensen/qemu/meson/mesonbuild/mesonmain.py", line 140, in run
    return options.run_func(options)
  File "/home/kbjensen/qemu/meson/mesonbuild/minstall.py", line 544, in run
    installer.do_install(datafilename)
  File "/home/kbjensen/qemu/meson/mesonbuild/minstall.py", line 362, in do_install
    self.install_targets(d)
  File "/home/kbjensen/qemu/meson/mesonbuild/minstall.py", line 458, in install_targets
    raise RuntimeError('File {!r} could not be found'.format(t.fname))
RuntimeError: File 'docs/qemu-qmp-ref.7' could not be found

I am reporting this from downstream from Gentoo as =app-emulation/qemu-6.0.0 at https://forums.gentoo.org/viewtopic-p-8609088.html.

I can include more information upon request.

Thank you!