Every caller of associate_uniform_storage was doing this to safety-check
that the uniform storage didn't get reallocated, except for
st_deserialise_ir_program().  This ended up leaving an opening for
use-after-free without hitting the assert in the hot-cache case (and I
found it on freedreno).  Having added it, it also reveals use-after-frees
in the drawpixels shader variant cases on llvmpipe and zink.

Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Part-of: <!8997>