kbuild: do not check for ancient modutils tools

scripts/depmod.sh checks for the output of '-V' expecting that it has
module-init-tools in it. It's a hack to prevent users from using
modutils instead of module-init-tools, that only works with 2.4.x
kernels. This however prints an annoying warning for kmod tool, that is
currently replacing module-init-tools.

Rather than putting another check for kmod's version, just remove it
since users of 2.4.x kernel are unlikely to upgrade to 3.x, and if they
do, let depmod fail in that case because they should know what they are
doing.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
Acked-by: WANG Cong <amwang@redhat.com>
Acked-By: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>