core: Fixed missing type variable in disk profiles

Fixed the missing type variable in disk profiles.
Also, fixed the bug for CPU profiles, since it share
the same common base class as disk profile.

Change-Id: I1f7500b557ada1ed78aa6d736018a5319142cd58
Bug-Url: https://bugzilla.redhat.com/1142887
Signed-off-by: Tomer Saban <tsaban@redhat.com>
Signed-off-by: Gilad Chaplik <gchaplik@redhat.com>