Change in flashrom[master]: ichspi: Split very long init function into two

[Nico Huber (Code Review)]

Attention is currently required from: Felix Singer, Edward O'Callaghan, Angel Pons, Anastasia Klimchuk, Nikolai Artemiev, Nicholas Chin.
Nico Huber has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/58735 )

Change subject: ichspi: Split very long init function into two
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Patch Set 7: Code-Review+1

(2 comments)

Patchset:

PS7: 
Now that this is tested I've found a ThinkPad T60 in one of my
laptop piles /o\ didn't try to boot it up yet, and I have no
idea whose it is oO

File ichspi.c:

https://review.coreboot.org/c/flashrom/+/58735/comment/fb5f3205_2049dfa2 
PS7, Line 1771: 	ich_generation = ich_gen;
              : 	ich_spibar = spibar;
These two are globals and also affect the ICH7 paths. I guess we
missed them because they are not used for ICH7 in the original init
function but only later during runtime.

I've also checked all other writes to globals on the common paths
of the original init function. There is only `swseq_data`, which is
not used for ICH7 (although I noticed that it could be used to
avoid code duplication in some cases, but that's for another day).