I found a solution! Use syslinux.efi and ldlinux.e64 from experimental
The files can be found in those package versions


Now UEFI netowrk boot works with my Thinkpad X230 with the new BIOS 2.73.
This means, there's no need for a loading a grubnetx64.efi and use
different config file for UEFI boot.

You can use the same configs in pxelinux.cfg/... created by
fai-chboot for PXE (legacy BIOS) and UEFI network boot.

regards Thomas

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