Ensure fid mda lists are populated correctly during vgextend.

Ensure fid mda lists are populated correctly during vgextend.

The vgextend path calls add_pv_to_vg().  Inside add_pv_to_vg(),
we must ensure we pass the correct mdas list into pv_setup(), as
copies of mdas are placed on the vg->fid list.  If we don't place
the mdas on the correct vg->fid list, the various counts may be
incorrect and the metadata balance algorithm will not work when
called from vg_write() path.

Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>