remove hard coded -j2 build argument

setup.py

@@ -62,7 +62,6 @@ class CMakeBuild(build_ext):
             build_args += ['--', '/m']
         else:
             cmake_args += ['-DCMAKE_BUILD_TYPE=' + cfg]
-            build_args += ['--', '-j2']
 
         env = os.environ.copy()
         env['CXXFLAGS'] = '{} -DVERSION_INFO=\\"{}\\"'.format(env.get('CXXFLAGS', ''),