[PATCH v3] drm/i915: Disable some extra clang warnings

[Chris Wilson]

Quoting Matthias Kaehlcke (2018-05-01 19:24:40)
> Commit 39bf4de89ff7 ("drm/i915: Add -Wall -Wextra to our build, set
> warnings to full") enabled extra warnings for i915 to spot possible
> bugs in new code, and then disabled a subset of these warnings to keep
> the current code building without warnings (with gcc). Enabling the
> extra warnings also enabled some additional clang-only warnings, as a
> result building i915 with clang currently is extremely noisy. For now
> also disable the clang warnings sign-compare, sometimes-uninitialized,
> unneeded-internal-declaration and initializer-overrides. If desired
> they can be re-enabled after the code has been fixed.
> 
> Signed-off-by: Matthias Kaehlcke <mka at chromium.org>
Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk>
-Chris