[PATCH wayland 0/2] Fix autotools doc build with Meson

[Daniel Stone]

Hi,
The horribly ugly second patch fixes the autotools doc build, which
started failing after adding Meson support. The presence of
$(srcdir)/doc/doxygen/xml, created to hold meson.build, caused autotools
to believe it no longer needed to create $(builddir)/doc/doxygen/xml,
then immediately fail when it tried to generate files into a directory
which doesn't exist.

We work around this by explicitly naming the absolute path of the build
directory in the target for mkdir, so autotools will no longer try to
consult VPATH for it.

The first patch simply removes the orphan pre-generated PNG files, which
were not referenced anywhere in the build, and did not get distributed
into tarballs.

Cheers,
Daniel