Make: Enable VLA check for kona kernel

Remove VLA (Variable Length Array) as warning-3 option and enable VLA by
default and treat VLA usage as errors. Update gcc-wrapper to ignore
upstream VLA warnings.

Signed-off-by: Channagoud Kadabi <ckadabi@codeaurora.org>
Change-Id: I85e9959c46b599c59a4a10415cd112222467cfca