mesa: Add a MUST_CHECK macro for __attribute__((warn_unused_result)).

In the kernel, this is called __must_check; all our attribute macros in
Mesa appear to be uppercase, so I went with that.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matt Turner <mattst88@gmail.com>
2 files changed