Drop Init_pg_query from exported symbol map

[stanhu]

Init_pg_query isn't actually exported, but _Init_pg_query is:

% nm pg_query_ruby.o | grep Init
0000000000000000 T _Init_pg_query
0000000000003b40 b _Init_pg_query.rb_intern_id_cache

A Ruby compiler compiled with XCode 14 without the flag -undefined,dynamic_lookup will see this error:

linking shared-object pg_query/pg_query.bundle
Undefined symbols for architecture arm64:
  "Init_pg_query", referenced from:
     -exported_symbol[s_list] command line option
     (maybe you meant: _Init_pg_query)
ld: symbol(s) not found for architecture arm64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [pg_query.bundle] Error 1

In #222, FreeBSD needed Init_pg_query, so we uses a specific symbol map file for FreeBSD.

Closes #255

[stanhu]

@lfittl macOS 12.6 fixes a zero-day vulnerability, and it appears that XCode 14 tends to be upgraded with that. I think this fix might be needed soon as more people start to use a Ruby interpreter compiled under XCode 14.

[lfittl]

@stanhu Hmm, I think this may require some more thinking, because the symbol name without the _ was an addition to fix the FreeBSD build: #222

Since we already have a special case for RUBY_PLATFORM =~ /darwin/ in extconf.rb we could either make a separate symbol file for macOS that only has the _ prefixed version, or (possibly better) we make a special file for FreeBSD and make the default to be only the _ prefixed version.

[stanhu]

@lfittl Ah, thanks. I should have looked at the history to see that. I added a FreeBSD symbol file.

[lfittl]

@stanhu Thanks!

In case you have the time, we'd also need to update the changelog for a new release - essentially a new version of #251 -- if you could work on that I should be able to stamp a release on Monday (otherwise I can also do that, just with a slight risk the release takes a bit longer)

[stanhu]

@lfittl Sure, done in #257.