fix dhcp lease entry wrong hostname (#4064)
fix dhcp lease entry wrong hostname (#4064)

When Guest VM add secondary nic,  will get wrong hostname "infiniteh" from dhcp server
infiniteh -->infinite
cat /etc/dhcphosts.txt
02:00:0b:ef:00:04,set:192_168_4_18,192.168.4.18,gumd-tes3,infiniteh
GabrielBrascher/cloudstack,GabrielBrascher/cloudstack,GabrielBrascher/cloudstack,GabrielBrascher/cloudstack,GabrielBrascher/cloudstack,GabrielBrascher/cloudstack,GabrielBrascher/cloudstack