[LTP] [PATCH v2 0/1] memcg_stress newlib porting

[Cristian Marussi]

This converts memcg stress tests and its helper to LTP newlib and
performs a general cleanup.

This patch is dependent on [1] since it factors out a common helper
to cgroup_lib.sh (introduced in [1])

Changes from v1:
----------------

 - Restored the original usage of SIGKILL to terminate memcg_process_stress
   helpers preocesses, after having had a look at what said in previous commit:
	9b9a6bb10258bc975bd1707b418699264d3bdcef

Cristian Marussi (1):
	[PATCH v2] [LTP] memcg_stress_test.sh: ported to newlib

[1]: http://lists.linux.it/pipermail/ltp/2018-December/010385.html