[L] Change in coreboot[main]: mb/asus/p8x7x-series: Add P8H77-M as a variant

[Keith Hui (Code Review)]

Attention is currently required from: Angel Pons, Fabian Groffen, Felix Singer, Keith Hui, Kevin Keijzer.

Keith Hui has posted comments on this change by Kevin Keijzer. ( https://review.coreboot.org/c/coreboot/+/78806?usp=email )

Change subject: mb/asus/p8x7x-series: Add P8H77-M as a variant
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Patch Set 6:

(2 comments)

File src/mainboard/asus/p8x7x-series/variants/p8h77-m/overridetree.cb:

https://review.coreboot.org/c/coreboot/+/78806/comment/c73d5d59_9a3232c1?usp... :
PS6, Line 16: 					device pnp 2e.1   off end	# Parallel
You want this on and configured. P8H77-M does have LPT port wired up.

https://review.coreboot.org/c/coreboot/+/78806/comment/446c31f0_56ca6f6e?usp... :
PS6, Line 29: 						drq 0x22 = 0xd7		# Power down UART B and LPT
Don't power down LPT.
```suggestion
    					drq 0x22 = 0xdf		# Power down UART B
```