to edge interrupt, like eth device, it can triger the interrupt again
when its IRQ in softirq entry queue or in timer list.
in current design, for sofrirq entry, it calls "list_del" before
"list_add_tail", to avoid the entry added twice.
so for interrupt delay timer, add to check if it is started
then just drop the next one; to avoid it enqueue twice.
Tracked-On: #2365
Signed-off-by: Minggui Cao <minggui.cao@intel.com>
Reviewed-by: Li, Fei1 <fei1.li@intel.com>