utils: LocalConfig: reduce message severity if file is missing

it is valid to have purely default without any configuration.

Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=1020675
Change-Id: If597acaf41049392a24d59549034af9e09c7616e
Signed-off-by: Alon Bar-Lev <alonbl@redhat.com>