stop_machine: Store task reference in a separate per cpu variable
stop_machine: Store task reference in a separate per cpu variable

To allow the stopper thread being managed by the smpboot thread
infrastructure separate out the task storage from the stopper data
structure.

Signed-off-by: Thomas Gleixner <00e4cf8f46a57000a44449bf9dd8cbbcc209fd2a@linutronix.de>
Cc: Peter Zijlstra <3fddac958924aef220f202ca567388ddab3f14a8@infradead.org>
Cc: Rusty Russell <df9728c9e5104131c08c7adb03af425394842596@rustcorp.com.au>
Cc: Paul McKenney <1e0ce936bb9b355d257bf5790d2513c3f28be22b@linux.vnet.ibm.com>
Cc: Srivatsa S. Bhat <5b23f8226e886b22344fc642373ea657dd596b63@linux.vnet.ibm.com>
Cc: Arjan van de Veen <9043bf4b08f6c93a2cb55d98c3494b123858348f@infradead.org>
Cc: Paul Turner <56b59ac50e86208fd62726b53c1d890b9a8ff058@google.com>
Cc: Richard Weinberger <35d495b41aa40f510ffcbb60365085b8b25447b5@linutronix.de>
Cc: Magnus Damm <1f369b7bccd13b930ed9aa83ec10be6225fd866f@gmail.com>
Link: 17df7d26993de753cb3483bac1f2ca928b7db627@linutronix.de
Signed-off-by: Thomas Gleixner <00e4cf8f46a57000a44449bf9dd8cbbcc209fd2a@linutronix.de>

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