Without this when compiling GLib with address sanitizer enabled, we'd
end up failing with this error:
==375535==ASan runtime does not come first in initial library list;
you should either link runtime to your application or manually preload
it with LD_PRELOAD.
Now, given that addressing the fix implies doing more radical changes,
it's just fine here to ignore ASAN to work on tools we use for building
gir files.
Generating gir and typelib files has inter-dependencies that may depend
on other elements.
For example, glib requires gobject and gdump generated files require
gmodule, so we've a cyclic dependency because gmodule requires gobject,
that requires glib.
To prevent this, let's just generate the introspection files at once in
a different meson file so that we don't have to deal with this.
As per this we could even revert commit fa37ab6d0 since gio is now
compiled before the gir files.
