glsl: Allow the use of determinant() in GLSL 1.50.

glsl: Allow the use of determinant() in GLSL 1.50.

We already implemented this for ES3, so we just need to turn it on.

Fixes 6 Piglit tests:
spec/glsl-1.50/compiler/built-in-functions/determinant-mat[234].{vert,frag}

Reviewed-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>