From: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
Change ima_post_path_mknod() definition, so that it can be registered as
implementation of the path_post_mknod hook.
Also, make sure that ima_post_path_mknod() is executed only if
(mode & S_IFMT) is equal to zero or S_IFREG.
Add this check to take into account the different placement of the
path_post_mknod hook (to be introduced) in do_mknodat(). Since the new hook
will be placed after the switch(), the check ensures that
ima_post_path_mknod() is invoked as originally intended when it is
registered as implementation of path_post_mknod.
Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx>