core: backend search returns only first page...

backend search returns only first page when given max=-1

Changing the code to get MAX INTEGER records when max = -1

Change-Id: I347c4fe5b4a569d16cb809fee3af7b39b36d9ede
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=1025320
Signed-off-by: Eli Mesika <emesika@redhat.com>