Uninline find_pid etc set of functions

The find_pid/_vpid/_pid_ns functions are used to find the struct pid by its
id, depending on whic id - global or virtual - is used.

The find_vpid() is a macro that pushes the current->nsproxy->pid_ns on the
stack to call another function - find_pid_ns().  It turned out, that this
dereference together with the push itself cause the kernel text size to
grow too much.

Move all these out-of-line.  Together with the previous patch this saves a
bit less that 400 bytes from .text section.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Paul Menage <menage@google.com>
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/kernel/capability.c b/kernel/capability.c
index 0d0d886..efbd9cd 100644
--- a/kernel/capability.c
+++ b/kernel/capability.c
@@ -96,7 +96,7 @@
 	int found = 0;
 	struct pid *pgrp;
 
-	pgrp = find_pid_ns(pgrp_nr, current->nsproxy->pid_ns);
+	pgrp = find_vpid(pgrp_nr);
 	do_each_pid_task(pgrp, PIDTYPE_PGID, g) {
 		target = g;
 		while_each_thread(g, target) {