[dsymutil] Don't emit .debug_pubnames and .debug_pubtypes

Consider the .debug_pubnames and .debug_pubtypes their own kind of
accelerator and stop emitting them together with the Apple-style
accelerator tables. The only reason we were still emitting both was for
(byte-for-byte) compatibility with dsymutil-classic.

 - This patch adds a new accelerator table kind "Pub" which can be
   specified with --accelerator=Pub.
 - This patch removes the ability to emit both pubnames/types and apple
   style accelerator tables. I don't think anyone is relying on that but
   it's worth pointing out.
 - This patch removes the --minimize option and makes this behavior the
   default. Specifying the flag will result in a warning but won't abort
   the program.

Differential revision: https://reviews.llvm.org/D99907