Meson: Do not build tests with nodelete/Bsymbolic-functions

-z nodelete breaks the libresourceplugin module usage in the resources.c
test, which expects to be able to unload it.

Make the Meson build match what the autotools build does: only pass
glib_link_flags to the headline libraries (glib-2.0, gio-2.0,
gobject-2.0, gthread-2.0, gmodule-2.0) and omit it from all other build
targets.

https://bugzilla.gnome.org/show_bug.cgi?id=788771

gthread/meson.build

@@ -18,7 +18,9 @@ libgthread = library('gthread-2.0',
   soversion : soversion,
   install : true,
   dependencies : [libglib_dep],
-  c_args : ['-DG_LOG_DOMAIN="GThread"' ] + glib_hidden_visibility_args)
+  c_args : ['-DG_LOG_DOMAIN="GThread"' ] + glib_hidden_visibility_args,
+  link_args : glib_link_flags,
+)
 
 pkg.generate(libraries : [libgthread, thread_dep],
   requires : ['glib-2.0'],