kernel.nix: boot.vesa implies nomodeset

[wmertens]

Without nomodeset the console is reset to 80x25 after Grub.

Motivation for this change

The standard configuration, even with boot.vesa = true, results in a tiny virtual console.

Things done

Tested this configuration on a VM; did not test this actual change.

[nixos-discourse]

This pull request has been mentioned on Nix community. There might be relevant details there:

https://discourse.nixos.org/t/big-virtual-console-solved/3176/3

[wmertens]

@7c6f434c You made this configurable 10 years ago, any opinion on this? :)

[7c6f434c]

I think this was before working kernel mode setting! And before UEFI which affects early initialisation of the display.

(and in the meantime I stopped using this area of NixOS boot code)

I would expect that configuring modeset and fbcon should provide better options than vesa — but I am not sure about virtual machines. I agree that if we do want VESA switching off modeset makes sense.