[XS] Change in coreboot[main]: Docs/tutorial: Do not install Ada compiler by default

[Nico Huber (Code Review)]

Attention is currently required from: Felix Held, Naveen Iyer.

Nico Huber has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/81296?usp=email )

Change subject: Docs/tutorial: Do not install Ada compiler by default
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Patch Set 2:

(1 comment)

Patchset:

PS2: 
I have tested some newer OS/package combinations with the tutorial instructions:
* Ubuntu 23.10 with gcc-9 / gcc-12 / no gcc pre-installed and various update-alternatives settings.
* Fedora 39 / 40 (testing)
* Alma Linux 9

On Ubuntu, when I either installed gcc, build-essentials or gnat, it overwrote any
link set by update-alternatives (not using it, just running the pointer down /o).

The Redhat-based ones didn't work because `cmp` was missing (should probably add
`diffutils` to the tutorial).

Alma needed `epel` to be installed ahead. But I expect enterprise users to know this.