Since commit 2aedcd09 ('kbuild: suppress annoying "... is up to
date." message'), $(call if_changed,...) is evaluated to "@:"
when there is nothing to do.
We no longer need to add "@:" after $(call if_changed,...) to
suppress "... is up to date." message.
Signed-off-by: Masahiro Yamada <email@example.com>
Signed-off-by: Michal Marek <firstname.lastname@example.org>