Switch to SPDX standard license name

Author: wagenrace

setup.py

@@ -44,7 +44,7 @@ def run(self):
                  url='http://github.com/clalancette/pycdlib',
                  author='Chris Lalancette',
                  author_email='[email protected]',
-                 license='LGPLv2',
+                 license='LGPL-2.1-only',
                  classifiers=['Development Status :: 5 - Production/Stable',
                               'Intended Audience :: Developers',
                               'License :: OSI Approved :: GNU Lesser General Public License v2 (LGPLv2)',