[gtk-osx] Fix python site-packages string for cases where we're not building python.

[John Ralls <jralls src gnome org>]

commit eb7a8c32274dd4a91f3a79bbebf470900c7b2156
Author: John Ralls <jralls ceridwen us>
Date:   Sun Sep 27 10:46:09 2020 -0700

    Fix python site-packages string for cases where we're not building python.

 jhbuildrc-gtk-osx | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/jhbuildrc-gtk-osx b/jhbuildrc-gtk-osx
index 27d2ac1..5572ab7 100644
--- a/jhbuildrc-gtk-osx
+++ b/jhbuildrc-gtk-osx
@@ -616,8 +616,8 @@ if 'python3' in modules or 'meta-gtk-osx-python3' in modules:
     os.environ['PYTHON'] = os.path.join(prefix, 'bin', 'python3')
     module_extra_env['pkg-config'] = {'PYTHON':sys.executable}
 else:
-    _python_ver = sys.version_info.major * 10 + sys.version_info.minor
-    _python_install_path = os.path.join(prefix, 'lib', str(_python_ver),
+    _python_ver = str(sys.version_info.major) + '.' + str(sys.version_info.minor)
+    _python_install_path = os.path.join(prefix, 'lib', 'python' + _python_ver,
                                         'site-packages')
     append_autogenargs('libxml2',
                        '--with-python-install-dir=' + _python_install_path)