setup: pass LD_LIBRARY_PATH to subprocess when determining version.

setup.py

@@ -121,6 +121,8 b" if os.path.isdir('.hg'):"
     env = {'PYTHONPATH': os.pathsep.join(pypath),
            'HGRCPATH': '',
            'LANGUAGE': 'C'}
+    if 'LD_LIBRARY_PATH' in os.environ:
+        env['LD_LIBRARY_PATH'] = os.environ['LD_LIBRARY_PATH']
     if 'SystemRoot' in os.environ:
         # Copy SystemRoot into the custom environment for Python 2.6
         # under Windows. Otherwise, the subprocess will fail with