libvirt 6.6.0 tarball breaks on Homebrew/MacOS

[Scott Shambarger]

The latest release at https://libvirt.org/sources/libvirt-6.6.0.tar.xz 
includes a configure script that breaks Homebrew (and other builds on 
MacOS/Darwin).  The breaking change is related to a new version of the 
file m4/libtool.m4; line 2648 was changed to:

   shrext_cmds='`test .$module = .yes && echo .bundle || echo .dylib`'

However, src/driver.c loads modules with ".so" extensions, at line 56:

     if (!(modfile = virFileFindResourceFull(name,
                                             "libvirt_driver_",
                                             ".so",

The released tarball for 6.5.0 had the same shrext_cmds as upstream 
libtool:

   shrext_cmds='`test .$module = .yes && echo .so || echo .dylib`'

Not sure where to submit the issue (as the m4 files aren't in libvirt 
source control)... it appears to only affect the distribution tarball.

Perhaps the tarball could be re-released with autoconf from the official 
upstream libtool? (2.4.6)

Thanks,
Scott

PS. MacPorts is unaffected as it runs autogen.sh... but that shouldn't 
be necessary with a distribution tarball :)