configure: allow PyPI access for python 'tooling' dependencies

We actually do not allow our meson requirements to be fetched online
because we strictly prefer the vendored version. Move the tooling group
installation to a different invocation that does allow PyPI to be
accessed when configure is run without explicitly disabling PyPI access.

This will allow QEMU to download and install python3-wheel for you if
you don't have it in your host environment.

Reported-by: Kevin Wolf <kwolf@redhat.com>
Reported-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Message-id: 20260225191255.955585-1-jsnow@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

configure

@@ -963,10 +963,12 @@ fi
 python="$python -B"
 mkvenv="$python ${source_path}/python/scripts/mkvenv.py"
 
-# Finish preparing the virtual environment using vendored .whl files
+# Finish preparing the virtual environment using vendored .whl files.
+# Even if PyPI is allowed, we disallow it here to force installation
+# from our preferred vendored versions.
 
 $mkvenv ensuregroup --dir "${source_path}/python/wheels" \
-     ${source_path}/pythondeps.toml meson tooling || exit 1
+     ${source_path}/pythondeps.toml meson || exit 1
 
 # At this point, we expect Meson to be installed and available.
 # We expect mkvenv or pip to have created pyvenv/bin/meson for us.
@@ -993,13 +995,19 @@ if test "$host_os" = "haiku" && test ! -e "$meson" ; then
     meson="$(cd pyvenv/non-packaged/bin; get_pwd)/meson"
 fi
 
-# Conditionally ensure Sphinx is installed.
-
 mkvenv_online_flag=""
 if test "$download" = "enabled" ; then
     mkvenv_online_flag=" --online"
 fi
 
+# Unconditionally install our tooling group. PyPI is allowed if enabled here.
+
+$mkvenv ensuregroup $mkvenv_online_flag \
+        --dir "${source_path}/python/wheels" \
+        ${source_path}/pythondeps.toml tooling || exit 1
+
+# Conditionally ensure Sphinx is installed.
+
 if test "$docs" != "disabled" ; then
     if ! $mkvenv ensuregroup \
          $(test "$docs" = "enabled" && echo "$mkvenv_online_flag") \