Add a malloca_of_list to Steel

[R1kM]

This PR adds a new function, called malloca_of_list to Steel. Similarly to what was done in Low*, this function takes a list literal, and allocates a new array statically initialized to the list literal. Similar restrictions as in Low* apply, i.e., the list must be statically known at compile-time.

The implementation of this function follows the same workflow as similar malloc functions in Steel, and is available for both Steel and SteelST.