defconfig: sdm845: Enable trace and scheduler options

Enable the IRQSOFF and PREEMPT tracers to help debug
irq and preemption latency problems. Also, enable the
debug options to panic on RT throttling as well as
other scheduler bugs.

Finally, enable the SCHED_AUTOGROUP option. This allows
auto-grouping of tty/terminal tasks to isolate them
from each other, providing interactivity improvements.

Change-Id: I637f1a0e62fffd8a49fdebb1fcd24de49a345a17
Signed-off-by: Vikram Mulukutla <markivx@codeaurora.org>