[L] Change in coreboot[main]: mb/asrock: Add Z77 Extreme4

[Keith Hui (Code Review)]

Attention is currently required from: Angel Pons, Riku Viitanen.

Keith Hui has posted comments on this change by Riku Viitanen. ( https://review.coreboot.org/c/coreboot/+/85772?usp=email )

Change subject: mb/asrock: Add Z77 Extreme4
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Patch Set 12:

(2 comments)

Patchset:

PS12: 
Do you have to do anything special to make a PS/2 mouse work?

File src/mainboard/asrock/z77_extreme4/early_init.c:

https://review.coreboot.org/c/coreboot/+/85772/comment/24c44145_ad2c92d2?usp... :
PS12, Line 10: if (CONFIG(CONSOLE_SERIAL))
The function will no-op itself if this config is not selected, so it's not necessary.