test/nvme: Increase the run time of hotplug.

Since we have increase 5s delay between insert device and setup.sh,
we also increase 5s for the run time of hotplug just make sure the
application will not exit before the hotplug actions.

Change-Id: If020824373ba82ccd1bc743993c5ddbcc50c6d0c
Signed-off-by: cunyinch <cunyin.chang@intel.com>
Reviewed-on: https://review.gerrithub.io/365529


Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>