More MANIFEST fixes

pythonn-ethtool/etherinfo_ipv6_obj.c was removed in
commit abab733.  The MANIFEST file needs to
reflect that as well.

Signed-off-by: David Sommerseth <davids@redhat.com>

Author: David Sommerseth

MANIFEST

@@ -5,7 +5,6 @@ python-ethtool/ethtool.c
 python-ethtool/ethtool-copy.h
 python-ethtool/etherinfo.c
 python-ethtool/etherinfo_obj.c
-python-ethtool/etherinfo_ipv6_obj.c
 python-ethtool/etherinfo_struct.h
 python-ethtool/etherinfo.h
 python-ethtool/etherinfo_obj.h