modules: fix incorrect percpu usage

Mainline does not need this fix, as commit
259354de fixed the problem by refactoring.

Should use per_cpu_ptr() to obfuscate the per cpu pointers (RELOC_HIDE is needed
for per cpu pointers).

Introduced by commit:

module.c: commit 6b588c18

This patch should be queued for the stable branch, for kernels 2.6.29.x to
2.6.33.x.  (tested on 2.6.33.1 x86_64)
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
CC: Randy Dunlap <randy.dunlap@oracle.com>
CC: Eric Dumazet <dada1@cosmosbay.com>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Peter Zijlstra <a.p.zijlstra@chello.nl>
CC: Tejun Heo <tj@kernel.org>
CC: Ingo Molnar <mingo@elte.hu>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Greg Kroah-Hartman <gregkh@suse.de>
CC: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kernel/module.c

@@ -555,7 +555,7 @@ static void percpu_modcopy(void *pcpudest, const void *from, unsigned long size)
 	int cpu;
 
 	for_each_possible_cpu(cpu)
-		memcpy(pcpudest + per_cpu_offset(cpu), from, size);
+		memcpy(per_cpu_ptr(pcpudest, cpu), from, size);
 }
 
 #else /* ... !CONFIG_SMP */