Change in coreboot[master]: ppc64/byteorder.h: define use of big endian

[Patrick Georgi (Code Review)]

Attention is currently required from: Maciej Pijanowski, Krystian Hebel, Ron Minnich.
Patrick Georgi has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/55037 )

Change subject: ppc64/byteorder.h: define use of big endian
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Patch Set 1: Code-Review+2

(2 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/55037/comment/4741e38b_2804ddc8 
PS1, Line 12: configuration is changed.
> I never use the make targets, I use buildgcc directly. See ./buildgcc -h: […]

Done

Patchset:

PS1: 
So, the ppc64 state in the tree is somewhat messy but trending towards Big Endian and LE proponents haven't chimed in, so let's move to BE consistently (which I'm very much in favor of personally, having "grown up" on SPARC :-) )

If there's a use case for ppc64le, we can see how to support both - later.