VLA are strongly discouraged in the kernel due to ambiguity they impose
on the limited stack space and security concerns over manipulating the
stack frame. Add -Wvla to our compiler flags so that CI rejects them.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180313004055.25411-2-chris@chris-wilson.co.uk