[M] Change in coreboot[master]: device/xhci: Factor out common PORTSC code

[Robert Zieba (Code Review)]

Attention is currently required from: Tarun Tuli, Subrata Banik, Nick Vaccaro, Angel Pons, Martin Roth.

Robert Zieba has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/67933 )

Change subject: device/xhci: Factor out common PORTSC code
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Patch Set 7:

(4 comments)

File src/include/device/xhci.h:

https://review.coreboot.org/c/coreboot/+/67933/comment/0ec23280_beaeef36 
PS5, Line 17: (1 << 26)
> can you use BIT(26) instead

Done

https://review.coreboot.org/c/coreboot/+/67933/comment/4dfb56f0_f37473b4 
PS5, Line 25: (5)
> u don't need braces

Done

https://review.coreboot.org/c/coreboot/+/67933/comment/fba23d4a_cdd989bb 
PS5, Line 26: 0xF
> use small case?

Done

https://review.coreboot.org/c/coreboot/+/67933/comment/ae56645e_74aa251c 
PS5, Line 36: !!
> Nit: Shouldn't be needed for bool.

Done