x11-libs/pixman: Pull in upstream fix for building with LLVM

BUG=chromium:793487
TEST=CQ

Change-Id: I573c06aa3b016369bf6936257158e7ec12d3b7b7
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/overlays/portage-stable/+/3266968
Tested-by: Fergus Dall <sidereal@google.com>
Auto-Submit: Fergus Dall <sidereal@google.com>
Commit-Queue: Jack Rosenthal <jrosenth@chromium.org>
Reviewed-by: Jack Rosenthal <jrosenth@chromium.org>
2 files changed