[S] Change in coreboot[main]: device: Add inline method to identify PATH_ROOT

[Patrick Rudolph (Code Review)]

Attention is currently required from: Arthur Heymans, Cliff Huang, Lance Zhao, Tim Wawrzynczak.

Patrick Rudolph has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/80169?usp=email )

Change subject: device: Add inline method to identify PATH_ROOT
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Patch Set 1:

(1 comment)

File src/include/device/device.h:

https://review.coreboot.org/c/coreboot/+/80169/comment/a035595f_396ebf1b :
PS1, Line 166: extern DEVTREE_CONST struct device	dev_root;
> Would comparing pointers with this not be a better idea? I suppose the compiler might even be able t […]

I don't see how the compiler could optimize something. I'd expect is_root_device() to be never called directly on the root device itself as this is rather pointless check. For all other devices it shouldn't matter if the pointer or the actual type is read and compared.