arc: vdk: Disable halt on reset

In recent VDKs ARC cores are configured as "run on reset"
which made existing kernel configuration outdated to effect that
slave cores never start execution of the code keeping only master
online.

With that fix we're again in sync with VDK platform.

And while at it we regenerate defconfig via savedefconfig so default
options are now excluded.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>