[libvirt] ESX [03/12]: Add esxDomainXMLToNative()

Extend and cleanup the VMX to domain XML mapping. Add the domain XML to VMX mapping functions. * src/esx/esx_driver.c: add esxDomainXMLToNative() * src/esx/esx_vmx.[ch]: add esxVMX_SCSIDiskNameToControllerAndID(), esxVMX_IDEDiskNameToControllerAndID(), esxVMX_FloppyDiskNameToController(), esxVMX_GatherSCSIControllers(), add basic handling for the VMX guestOS entry to distinguish between i686 and x86_64, make SCSI virtualDev VMX entry optional as it should be, map the VMX networkName entry to the domain XML interface bridge name, add basic mapping for serial devices in pipe mode, add several esxVMX_Format*() functions