driver-core: document restrictions on device_rename()
driver-core: document restrictions on device_rename()

Add text, courtesy of Kay Sievers, that provides some background on
device_rename() and why it shouldn't be used.

Signed-off-by: Timur Tabi <4ea348ebd818e67772cb0086d44dc1b57ba54129@freescale.com>
Signed-off-by: Greg Kroah-Hartman <4645f7897fd33786a2ee1264d590b3c400559d85@suse.de>

KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs