Documentation: Fix spelling errors

These issues were found and fixed by codespell, a useful tool for
finding spelling errors.

Signed-off-by: Martin Roth <martin@coreboot.org>
Change-Id: If2a8e97911420c19e9365d5c28810b998f2c2ac8
Reviewed-on: https://review.coreboot.org/c/coreboot/+/58078
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

Documentation/contributing/coding_style.md

@@ -801,7 +801,7 @@ There are a LOT of cpu cycles that can go into these 5 milliseconds.
 
 A reasonable rule of thumb is to not put inline at functions that have
 more than 3 lines of code in them. An exception to this rule are the
-cases where a parameter is known to be a compiletime constant, and as a
+cases where a parameter is known to be a compile time constant, and as a
 result of this constantness you *know* the compiler will be able to
 optimize most of your function away at compile time. For a good example
 of this later case, see the kmalloc() inline function.