mercurial: old Xcode clang should be blacklisted for 10.6 Rosetta

[barracuda156]

By default on 10.6.8 Rosetta mercurial invokes Clang, which is obviously wrong:

--->  Building mercurial
Executing:  cd "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_mercurial/mercurial/work/mercurial-6.2.1" && make -j6 -w all build-chg PYTHON=/opt/local/Library/Frameworks/Python.framework/Versions/3.10/bin/python3.10 COMPILERFLAG=-j6 
make: Entering directory `/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_mercurial/mercurial/work/mercurial-6.2.1'
/opt/local/Library/Frameworks/Python.framework/Versions/3.10/bin/python3.10 setup.py  build -j6
make -C doc
make -C contrib/chg
make[1]: Entering directory `/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_mercurial/mercurial/work/mercurial-6.2.1/contrib/chg'
make[1]: Nothing to be done for `all'.
make[1]: Leaving directory `/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_mercurial/mercurial/work/mercurial-6.2.1/contrib/chg'
make[1]: Entering directory `/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_mercurial/mercurial/work/mercurial-6.2.1/doc'
make[1]: Nothing to be done for `all'.
make[1]: Leaving directory `/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_mercurial/mercurial/work/mercurial-6.2.1/doc'
/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_mercurial/mercurial/work/mercurial-6.2.1/setup.py:1635: DeprecationWarning: distutils Version classes are deprecated. Use packaging.version instead.
  xcode4 = version.startswith('Xcode') and StrictVersion(
/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_mercurial/mercurial/work/mercurial-6.2.1/setup.py:1637: DeprecationWarning: distutils Version classes are deprecated. Use packaging.version instead.
  ) >= StrictVersion('4.0')
running build
running build_mo
running build_py
running build_ext
building 'mercurial.cext.base85' extension
building 'mercurial.cext.bdiff' extension
/usr/bin/clang -fno-strict-aliasing -Wsign-compare -fno-common -dynamic -DNDEBUG -g -fwrapv -O3 -Wall -pipe -Os -arch ppc -isysroot/ -Imercurial -I/opt/local/Library/Frameworks/Python.framework/Versions/3.10/include/python3.10 -c mercurial/cext/base85.c -o build/temp.macosx-10.6-ppc-cpython-310/mercurial/cext/base85.o
building 'mercurial.cext.mpatch' extension
/usr/bin/clang -fno-strict-aliasing -Wsign-compare -fno-common -dynamic -DNDEBUG -g -fwrapv -O3 -Wall -pipe -Os -arch ppc -isysroot/ -Imercurial -I/opt/local/Library/Frameworks/Python.framework/Versions/3.10/include/python3.10 -c mercurial/bdiff.c -o build/temp.macosx-10.6-ppc-cpython-310/mercurial/bdiff.o
building 'mercurial.cext.parsers' extension
building 'mercurial.thirdparty.zope.interface._zope_interface_coptimizations' extension
building 'mercurial.cext.osutil' extension
clang: warning: not using the clang compiler for the 'powerpc' architecture
clang: warning: not using the clang compiler for the 'powerpc' architecture

We need this in Portfile (either blacklist ancient clang altogether or at least for PPC):

compiler.blacklist-append \
                    *gcc-4.0 *gcc-4.2 {clang < 421}

[Dan Villiom Podlaski Christiansen <danchr@…>]

In e4f63043cbe30e0071c2e59e53afe27f1357900e/macports-ports (master):

mercurial: update to 6.4.4; use python311

While at it, adjust compiler blacklist as requested in
#65938

Closes: #67341
Closes: #65938