Get rid of f_id_of_upvalue and f_id_of_local

[hugomg]

This information is only necessary in the coder, to decide whether to emit a CallStatic or a CallDyn. Currently, we compute this in the to_ir and then have to accurately update it across all optimization passes. This is easy to get wrong (for example, see #522). A better design might be to compute the information only when we reach the coder. Have an analysis pass that identifies the static calls, based on the use-def chains.