This issue was initially detected by PVS Studio (issue number V547) and fixed
as part of Google Code-in 2019.
The initial problem was the calculate_cpu_conversion_factor function
which had been copied in the BIOS and EFI versions of the boot code.
Further investigation led to more duplicated or very similar functions
being identified.
Introduce an arch_cpu.h for the x86 boot platform to group these things
in a single place, and adjust the BIOS and EFI code to call into that.
Note that the BIOS and EFI code is still a little platform specific,
ideally there should be a boot_arch_cpu_init() function for each
architecture as already done for openfirmware and u-boot.
Also remove some irrelevant comments from copypasted files for other
architectures, as that was filling my git grep with useless noise.
Change-Id: I16d815f0bf015cec0b4e03cc14f3cc447c7164c5
Reviewed-on: https://review.haiku-os.org/c/haiku/+/1985
Reviewed-by: Adrien Destugues <pulkomandy@gmail.com>
