quota: remove dependency on util-linux

The dependency on util-linux is only present in Config.in, and not in
quota.mk, and quota indeed builds properly without util-linux. It
could be a runtime dependency, but there is no indication that it is
the case, and I don't see why quota would run-time depend on
util-linux utilities.

Looking back at when the quota package was introduced, in one of the
preliminary patch, he following explanation was given by the original
author:

  [Update: I added check for util-linux mount because
   it support usrquota and grpquota mount options.]

But I still don't see why usrquota and grpquota mount options would be
the source of a dependency of the quota utilities on util-linux. Here
is what the util-linux mount man page says about those two mount
options:

   grpquota|noquota|quota|usrquota

         These options are accepted but ignored.  (However, quota
         utilities may react to such strings in /etc/fstab.)

So indeed, the quota tools will look at /proc/mounts and see if those
options are used for certain mount points, but that doesn't create a
dependency of quota on util-linux.

Therefore, this commit gets rid of the dependency of quota on
util-linux. It allows to re-enable quota on Microblaze, since this
dependency was inherited from util-linux.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>