x86, mm: Fix section mismatch in tlb.c

Mark tlb_cpuhp_notify as __cpuinit. It's basically a callback
function, which is called from __cpuinit init_smp_flash(). So -
it's safe.

We were warned by the following warning:

 WARNING: arch/x86/mm/built-in.o(.text+0x356d): Section mismatch
 in reference from the function tlb_cpuhp_notify() to the
 function .cpuinit.text:calculate_tlb_offset()
 The function tlb_cpuhp_notify() references
 the function __cpuinit calculate_tlb_offset().
 This is often because tlb_cpuhp_notify lacks a __cpuinit
 annotation or the annotation of calculate_tlb_offset is wrong.
Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: Shaohua Li <shaohua.li@intel.com>
LKML-Reference: <AANLkTinWQRG=HA9uB3ad0KAqRRTinL6L_4iKgF84coph@mail.gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/mm/tlb.c

@@ -251,7 +251,7 @@ static void __cpuinit calculate_tlb_offset(void)
 	}
 }
 
-static int tlb_cpuhp_notify(struct notifier_block *n,
+static int __cpuinit tlb_cpuhp_notify(struct notifier_block *n,
 		unsigned long action, void *hcpu)
 {
 	switch (action & 0xf) {