network/nfs_stress/nfs03: use nfs_lib.sh, run over IPv6

Also, remove setting LTPROOT directory in stress.part1 runtest file
for nfs02 and nfs03.

Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Acked-by: Cyril Hrubis <chrubis@suse.cz>
3 files changed