bits-2073 released with these changes:

• efi: Support EFI_IP4_CONFIG2_PROTOCOL and associated data structures

• _socket: Use EFI_IP4_CONFIG2_PROTOCOL if available, falling back to EFI_IP4_CONFIG_PROTOCOL

  BIOSes based on current versions of EDK2, including current OVMF, only support EFI_IP4_CONFIG2_PROTOCOL, and drop support for EFI_IP4_CONFIG_PROTOCOL. Support configuring IPv4 via the newer protocol, falling back to the older protocol for compatibility with existing BIOSes.

  In either case, reuse the existing IPv4 configuration if present, and only kick off DHCP if not already configured. This also allows systems that require manual IPv4 configuration to perform such configuration (via the EFI shell, the BITS Python interpreter, or any other means) and subsequently use that configuration with BITS.