packagegroup-base : Add nfs-utils for mel

mount command with option -t nfs wasn't working as
it expects to find mount.nfs provided by package
nfs-utils. Adding that package on rootfs solves
the problem.

JIRA : http://jira.alm.mentorg.com:8080/browse/SB-2739

Signed-off-by: Yasir-Khan <yasir_khan@mentor.com>
Merge pull request #177 from Yasir-Khan/mel-nfs

nfs support for mel