i965: Add missing _NEW_BUFFERS dirty bit in Gen7 SBE state.

This is needed to compute render_to_fbo.  It even has the comment.

NOTE: This is a candidate for stable branches.

Reviewed-by: Eric Anholt <eric@anholt.net>
(cherry picked from commit bd87441ac028068f422e2c96b39f93644a0f246f)
1 file changed