anv/pipeline: Get rid of the kernel pointer fields

anv/pipeline: Get rid of the kernel pointer fields

Now that we have anv_shader_bin, they're completely redundant with other
information we have in the pipeline.  For vertex shaders, we also go
through way too much work to put the offset in one or the other field and
then look at which one we put it in later.

Reviewed-by: Timothy Arceri <timothy.arceri@collabora.com>
Reviewed-by: Kristian H. Kristensen <hoegsberg@google.com>