The overflow check for the bandwidth parameter did not jump to the
cleanup label.
Additionally virsh should use vshError instead of virReportError.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1206987
Signed-off-by: Luyao Huang <lhuang@redhat.com>
(cherry picked from commit 390f218b83513a00b81549eb66854d8b263cb014)