pidns: remove now unused find_pid function.

This one had the only users so far - the kill_proc, which is removed, so
drop this (invalid in namespaced world) call too.

And of course - erase all references on it from comments.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 134cb5c..182da15 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1718,7 +1718,7 @@
  * find_task_by_pid():
  *      finds a task by its global pid
  *
- * see also find_pid() etc in include/linux/pid.h
+ * see also find_vpid() etc in include/linux/pid.h
  */
 
 extern struct task_struct *find_task_by_pid_type_ns(int type, int pid,