HW_CI test list: Check system uptime average

This commit extends the hardware CI test bucket by verifying the average
system uptime after a boot is less than an arbitrary threshold. A
threshold of 3 minutes was selected by experimentation - a healthy
system typically had an uptime of around 2.5 minutes.

Change-Id: I6266330ca6b912b4f68787fc141d1945f6b13e16
Signed-off-by: Michael Tritz <mtritz@us.ibm.com>
Signed-off-by: Saqib Khan <khansa@us.ibm.com>
2 files changed