Regression test portability: LVM

Skip any test involving LVM on NetBSD as LVM is not supported

BUG: 1129939
Change-Id: I2237bae1128d1a81047c9ff7f905431156daf8b7
Signed-off-by: Emmanuel Dreyfus <manu@netbsd.org>
Reviewed-on: http://review.gluster.org/8556
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>