arb_fragment_program: Test KIL using result of SLT
Reproduces a bug caused by a bad optimization that would cause part of the condition for the KIL instruction to be omitted. This test uses a similar pattern to a shader from Euro Truck Simulator 2 that is in my shader-db.
I believe this is the underlying problem of mesa#1346 (closed). There will be more information in a Mesa MR that is coming soon.
This test fails on versions of Mesa that include 68420d8322c ("nir: Simplify min and max of b2f") and 9167324a86b ("nir/algebraic: Mark some logic-joined comparison reductions as exact").