swrast: Build fix for Solaris

Fixes regression from commit 5b2d3480f57168d50ad24cf0b8c9244414bd3701

Cc: "10.5 10.6" <mesa-stable@lists.freedesktop.org>
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Reviewed-by: Jeremy Huddleston Sequoia <jeremyhu@apple.com>
2 files changed