Previously, some of the code in SF erroneously used bitfields based on
the gl_frag_attrib enum when actually referring to vertex results.
This worked, because coincidentally the particular enum values being
used happened to match between gl_frag_attrib and gl_vert_result. But
it was fragile, because a future change to either gl_vert_result or
gl_frag_attrib would have made the enum values stop matching up. This
patch switches the SF code to use the correct enum.
Reviewed-by: Eric Anholt <eric@anholt.net>
Paul Berry
aafe2cdf86