Clean up LAP peephole logging

Clean up LAP peephole logging

Make `byte-compile-log-lap` more robust and produce nicer output.
This is of interest for Elisp compiler maintainers only.

* lisp/emacs-lisp/byte-opt.el (bytecomp--log-lap-arg): New.
(byte-compile-log-lap-1): Extract argument conversion and rewrite
in a more modern way, fixing bugs.  In particular, tags are now
displayed as "X:" where X is the tag number, and that tag number
is shown as argument to goto-like ops.
(byte-optimize-lapcode): Clean up and simplify logging, producing
useful information when `byte-optimize-log` is `byte` as intended.