x86: fix __cpuinit/__init tangle in init_thread_xstate()

Impact:	fix incorrect __init annotation

This patch removes the following section mismatch warning. A patch set
was send previously (http://lkml.org/lkml/2008/11/10/407). But
introduce some other problem, reported by Rufus
(http://lkml.org/lkml/2008/11/11/46). Then Ingo Molnar suggest that,
it's best to remove __init from xsave_cntxt_init(void). Which is the
second patch in this series. Now, this one removes the following
warning.

WARNING: arch/x86/kernel/built-in.o(.cpuinit.text+0x2237): Section
mismatch in reference from the function cpu_init() to the function
.init.text:init_thread_xstate()
The function __cpuinit cpu_init() references
a function __init init_thread_xstate().
If init_thread_xstate is only used by cpu_init then
annotate init_thread_xstate with a matching annotation.
Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/kernel/i387.c

@@ -58,7 +58,7 @@ void __cpuinit mxcsr_feature_mask_init(void)
 	stts();
 }
 
-void __init init_thread_xstate(void)
+void __cpuinit init_thread_xstate(void)
 {
 	if (!HAVE_HWFP) {
 		xstate_size = sizeof(struct i387_soft_struct);