Commit 3ac68a93fd (help: add --config to list all available config -
2018-05-26) makes generate-cmdlist.sh adds a new input source
config.txt but it's not a Makefile dependency. Any changes in
config.txt will not trigger command-list.h regeneration and the config
list in this file becomes outdated. Correct the dependency.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>