Remove the compression suffix macros and move them directly into the
compress_type array.
Simplify the compression args arrays at the expense of a __DECONST call when
copying them into the execv array.
Add explicit sizes to the suffix and compression args arrays to catch
overflows at compile-time.
Remove the nested loop in do_zipwork. The COMPRESS_* macros can directly
index the compress_types array, so the outer loop is not needed.