[PATCH 18/18] nvme: move chardev and sysfs interface to common code

[Jon Derrick]

> > Why?
> 
> Well, for starters, it's good practice to have strings like this in a
> #define.
> 
> I can send a patch to redefine this and 0x4E564D65 in the nvme.h.
IMO, make the hex "NVMe" a #define or at least keep its comment.
Keep "nvme" in the class_create call because there is no point in obfuscating that :)