tile: Reorganize _switch_to()

Move the simulator bits into finish_arch_post_lock_switch() and
properly call __switch_to() from _switch_to().

Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
Cc: <efault@gmx.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1438783412-10990-1-git-send-email-cmetcalf@ezchip.com


[ Made it a delta to: fe363adb ("sched, tile: Remove finish_arch_switch"). ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>