[PATCH 0/5] MR230: hlsl: Replace bare list pointers with hlsl_block, part 1.

[Zebediah Figura (＠zfigura)]

This introduces temporary helpers block_to_list and list_to_block.

The job of block_to_list(), at least, could be done by simply writing
"&block->instrs" everywhere instead. Using the helper instead ensures that
all of these instances will eventually be converted.