These kinds of warnings are inevitable for generic macros.

For the case of TV_DICTITEM_STRUCT, we can't just pass `1` because:
https://github.com/neovim/neovim/pull/8142#discussion_r175262436
> this variant will trigger array overrun warnings from various static analyzers.

Add a way to collect list usage statistics

New logging is guarded by cmake LOG_LIST_ACTIONS define. To make it more
efficient it is allocated as a linked list with chunks of length
2^(7+chunk_num); that uses basically the same idea as behind increasing kvec
length (make appending O(1) (amortized)), but reduces constant by not bothering
to move memory around what realloc() would surely do: it is not like we need
random access to log entries here to justify usage of a single continuous memory
block.