Regression test portability: ps

ps aux is truncated to the terminal width on NetBSD, Use ps auxww to
avoid that

BUG: 764655
Change-Id: I28a2fc23e2823dd6524a72da30111b86fc4bfa7b
Signed-off-by: Emmanuel Dreyfus <manu@netbsd.org>
Reviewed-on: http://review.gluster.org/8281
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Harshavardhana <harsha@harshavardhana.net>
Tested-by: Harshavardhana <harsha@harshavardhana.net>