handbook/x11: Suggest kld_list with nvidia-modesetting

[debdrup]

Summary

Since the previous instructions could lead to people having to blacklist
the nvidia module from loader in case it breaks something, switch to
using kld_list in /etc/rc.conf instead.

While here, also suggest using nvidia-modesetting, as this hooks into
the KMS bits in the kernel, which are present in all supported branches.

Reported by: Simon Adameit <simon at simonadameit.com>

[pauamma_gundo.com]

Grammar and spelling look fine to me at a glance.

[debdrup]

Sorry, I meant to tag this planning changes earlier.

It turns out the X11 chapter can be redone, since Xorg auto-configuration can take care of almost everything if you use kld_list and drm-kmod modules or nvidia-modeset from graphics/drm-kmod and x11/nvidia-driver respectively.

We'll need a short section on BusID which I'll add later on, for if people have hybrid setups like an iGPU and dGPU equipped laptop.

[ceri]

Keen to see some version of this committed, as the current instructions left my laptop unbootable.
Am testing the rest of this.

[carlavilla]

@debdrup I think we can close this, right?
It's fixed in the last version of the chapter.