[tz] zdump broken with -DUSE_LTZ=0

I tried updating the copy of tzcode in glibc. I found that as of the latest release and current git, zdump doesn't build with -DUSE_LTZ=0, because that configuration disables the inclusion of private.h, which defines the INITIALIZE macro which zdump now uses unconditionally. (There's also a -Wundef issue with the "#if !HAVE_POSIX_DECLS", as that's also only defined in private.h, but that's easy to work around.) -- Joseph S. Myers joseph@codesourcery.com