This fixes the same issue as 8bef6204, which became an issue again
after 31d0399c.
Besides, it is not really helpful to print just "GEN " (_without_
"perl.mak").
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>