cpuidle: add cpuidle_unregister_driver() error check
cpuidle: add cpuidle_unregister_driver() error check

Assure that cpuidle_unregister_driver() will not clobber
the registered driver if unregistered by somebody else.

Signed-off-by: Len Brown <b060cfa1096cc6e8be83699ddb4ed8a77dd63af5@intel.com>

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