Table 220 - output ports action doesn't clear for vm deletion/ovs restart

Description
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1.Load newton setup via Devstuck.(Host1=controller+compute,Host2=compute)
**As part of setup establishment few vm lunce and delete
2.Ovs restart to compute+control
3.Dump pipeline of compute(Host2)
4.Ovs restart to compute(Host2)
5.Dump pipeline of compute(Host2)

Defects
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1.it can be seen that action for output_port exist in table 220 altouge no vm in nova list.
2.Action for output_port in table 220 should delete for no vm's in setup.

Before ovs restart(nova list=empty)
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table=220 priority=7 reg6=0xe0000900 actions=output:12
table=220 priority=7 reg6=0xe0000b00 actions=output:26
table=220 priority=7 reg6=0xe0001000 actions=output:32
table=220 priority=7 reg6=0xe0001800 actions=output:34
After ovs restart(nova list=empty)
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table=220 priority=7 reg6=0xe0000900 actions=output:8
table=220 priority=7 reg6=0xe0000b00 actions=output:20
table=220 priority=7 reg6=0xe0001000 actions=output:21
table=220 priority=7 reg6=0xe0001800 actions=output:23