x86: move init_memory_mapping() to common mm/init.c, build fix on 32-bit PAE

Impact: build fix

Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1236257708-27269-14-git-send-email-penberg@cs.helsinki.fi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 1669693..5e5126e 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -605,7 +605,7 @@
 }
 early_param("noexec", noexec_setup);
 
-static void __init set_nx(void)
+void __init set_nx(void)
 {
 	unsigned int v[4], l, h;