narrowbundle2: drop legacy getcgkwargs variable

I think this was around as part of support for some older hg
internals. It's not needed any more.

Differential Revision: https://phab.mercurial-scm.org/D2386

hgext/narrow/narrowbundle2.py

@@ -219,13 +219,12 b' def getbundlechangegrouppart_narrow(bund'
                                     bundlecaps=None, b2caps=None, heads=None,
                                     common=None, **kwargs):
     cgversions = b2caps.get('changegroup')
-    getcgkwargs = {}
     if cgversions:  # 3.1 and 3.2 ship with an empty value
         cgversions = [v for v in cgversions
                       if v in changegroup.supportedoutgoingversions(repo)]
         if not cgversions:
             raise ValueError(_('no common changegroup version'))
-        version = getcgkwargs['version'] = max(cgversions)
+        version = max(cgversions)
     else:
         raise ValueError(_("server does not advertise changegroup version,"
                            " can't negotiate support for ellipsis nodes"))