Load the glibc library only once for Pyroute2
Load the glibc library only once for Pyroute2

Load the glibc library only once, needed in the Pyroute2 methods to
create and delete a network namespace.

Change-Id: I95b7b7008f4788a98ef871c4b7aecea839ff2310
Closes-Bug: #1854462

mahak/neutron,mahak/neutron,openstack/neutron,mahak/neutron,openstack/neutron,openstack/neutron