Delete idle_timestamp from irq_cpustat_t as it's an unread relic.
Signed-off-by: NAkira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: NKiyoshi Owada <owada.kiyoshi@jp.panasonic.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>