ktest: Set do_not_reboot=y for CONFIG_BISECT_TYPE=build

Currently setting do_not_reboot is triggered by simple builds and bisect
builds, but not config bisect builds.

Link: http://lkml.kernel.org/r/20170717001630.10518-3-swood@redhat.com



Signed-off-by: Scott Wood <swood@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>