Use new __gitcomp_nl; this is the last place that uses COMPREPLY and
compgen directly outside __gitcomp* functions.
Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com> Acked-by: SZEDER Gábor <szeder@ira.uka.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>