This rips out the dwz support by default to make Roland happy, or at
least a little bit less cranky :) Unless one uses --enable-dwz no dwz
multi-file support code is included. The DW_FORM_GNU_ref_alt/strp_alts
are still recognized, but any usage in libdw will just produce an error
because no alt files are ever looked up or opened.
Committed and pushed.