defconfig: arm64: Enable couple of debugging config flags

PANIC_ON_RT_THROTTLING flag trigger panic when RT throttling.
And PANIC_ON_SCHED_BUG config flag panic scheduling
while atomic and sleeping from invalid context.

Change-Id: I39ac0fe0f7be4e73a1a9d2aff35d11155c48ed77
Signed-off-by: Prasad Sodagudi <psodagud@codeaurora.org>