[pm] Detect darwin and change dl_load accordingly
[pm] Detect darwin and change dl_load accordingly

The dl_load_flags on Darwin are different than the ones from
the other platforms, so we need to detect the operating system
and change the return value of dl_load_flags() accordingly.

GNOME/perl-Champlain,potyl/champlain,Distrotech/libchamplain,GNOME/libchamplain,PabloCastellano/libchamplain,PabloCastellano/libchamplain,StanciuMarius/Libchamplain-map-wrapping,Distrotech/libchamplain,Distrotech/libchamplain,potyl/champlain,GNOME/perl-Gtk2-Champlain,Distrotech/libchamplain,PabloCastellano/libchamplain,GNOME/perl-Gtk2-Champlain,StanciuMarius/Libchamplain-map-wrapping,Distrotech/libchamplain,StanciuMarius/Libchamplain-map-wrapping,StanciuMarius/Libchamplain-map-wrapping,PabloCastellano/libchamplain,GNOME/libchamplain,potyl/champlain,StanciuMarius/Libchamplain-map-wrapping,potyl/champlain,PabloCastellano/libchamplain,GNOME/perl-Champlain