i965: Add texrect scale parameters before pointers to ParameterValues.

i965: Add texrect scale parameters before pointers to ParameterValues.

If adding scale parameters during program compile caused a realloc of
ParameterValues, then the driver uniform storage set up by
_mesa_associate_uniform_storage() would point to potentially freed
memory.

Note that this uses TexturesUsed, which may change at runtime for GLSL
when sampler uniforms change.  This is a flaw in our handling of texrect
in general, and not one I'm fixing currently.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>