WIP: turnip: support pipeline memory cache

Implement 2 caches inside, which are:
One is for nir shaders and another one is for ir3_shader_variants.

The key for the nir cache contains(what needs to be hashed):

• struct tu_shader_module

The key for the ir3_shader_variant contains(what needs to be hashed):

• struct ir3_shader_key
• cache_key from ir3_shader
• binning_pass (bool)

Note that this patch doesn't use the default cache(mem_cache).

I disable this feature by default and add new debug option to turn it on by the 2nd patch.