Add delay before powering on in CI test

Added 30 seconds delay to wait for mailbox to reset before powering on
to minimize the watchdog reset error.

Resolves openbmc/openbmc-test-automation#452

Change-Id: I654c1883dd83da1d0a13b948be36d8b5e404a59d
Signed-off-by: George Keishing <gkeishin@in.ibm.com>
1 file changed