Do not rely on the fact that components in module_path to have

Do not rely on the fact that components in module_path to have
trailing slash.  The previous commit changed the default value
of kern.module_path to use boot loader variable `module_path',
whose default value doesn't have trailing slashes, so kldload
failed unless you explicitly define module_path to have
trailing slashes.

Noticed-by: Thomas Nikolajsen <thomas.nikolajsen at mail.dk>