[Mesa-dev] shader-db MR: run: set NULL as initial value for binding_list

[apinheiro]

Without it, under some specific compilation options, it can be 
initialized to NULL or to garbage. On the latter case, if the shader 
doesn't require a binding_list, would cause a crash later when it 
attempts to be used.

https://gitlab.freedesktop.org/mesa/shader-db/merge_requests/7