This reverts commit d761f0c5.

Patch: "cpu: Register a generic CPU device on architectures that currently do not"
(sha1: 9f13a1fd)

selects GENERIC_CPU_DEVICES for Microblaze which register cpu.
My patch was done in the same time that's why cpu was registered twice which
caused this warning log:

------------[ cut here ]------------
WARNING: at fs/sysfs/dir.c:481 sysfs_add_one+0xb0/0xdc()
sysfs: cannot create duplicate filename '/devices/system/cpu/cpu0'
Modules linked in:
...
Signed-off-by: Michal Simek <monstr@monstr.eu>