Per NSXv3 API MacManagementSwitchingProfile schema, the POST MAC
Learning switching profile API should use mac_change_allowed not
source_mac_change_allowed.
Also, the mac_change_allowed should not be used in creating MAC
Learning switching profile. That param is designed for used in ESX
to change MAC address once. In MAC Learning use case, as long as
mac_learning is enabled, mac_change_allowed doesn't matter.
Change-Id: Icd88f222c559c15949d9b9d1a600f78e89715bae