iPXE on DELL 7010 in UEFI mode

[NiKiZe]

There are a few recent commits that reminds me of something similar
https://git.ipxe.org/ipxe.git/commit/d46...6703e3d178
https://git.ipxe.org/ipxe.git/commit/74d...11d93b6a39

The actual message "refusing to start during disconnection" that you see was introduced in the 74d90 commit

Here the issue was that the firmware didn't allow for the device to be disconnected, so it just hung.
During troubleshooting I tried to document at least some of the steps: http://ipxe.org/appnote/efidriverdisconnect
This would confirm if it is a pure firmware issue or not.

The reason it works on some machines but not others is most certainly due to different implementations of the EFI firmware. With that said it might be some way to work around it, but no good solution yet, as can be seen in the above 2 commits.