[Trusty][PATCH] UBUNTU: SAUCE: (no-up) Fix build failure on arm64

[dann frazier]

commit c3208d7fd18a ("ptrace: fix fork event messages across pid namespaces")
breaks building on arm64 due to a bad interaction (header loop) with
c9c5b652e3d8 ("UBUNTU: ubuntu:aufs3 -- (no-up) aufs3-mmap.patch).

Fix this by avoiding the new include and just adding the needed prototype.

Reference: https://lists.ubuntu.com/archives/kernel-team/2014-August/047024.html
Signed-off-by: dann frazier <dann.frazier at canonical.com>
---
 include/linux/ptrace.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h
index cc79eff..8314249 100644
--- a/include/linux/ptrace.h
+++ b/include/linux/ptrace.h
@@ -5,9 +5,10 @@
 #include <linux/sched.h>		/* For struct task_struct.  */
 #include <linux/err.h>			/* for IS_ERR_VALUE */
 #include <linux/bug.h>			/* For BUG_ON.  */
-#include <linux/pid_namespace.h>	/* For task_active_pid_ns.  */
 #include <uapi/linux/ptrace.h>
 
+extern struct pid_namespace *task_active_pid_ns(struct task_struct *tsk);
+
 /*
  * Ptrace flags
  *
-- 
2.0.1