i386: Misc cpuinit annotations

msr_class_cpu_callback() can be marked __cpuinit, being the notifier
callback for a __cpuinitdata notifier_block. So can be marked
msr_device_create() too, called only from the newly-__cpuinit
msr_class_cpu_callback() or from __init-marked msr_init().

[ tglx: arch/x86 adaptation ]

Signed-off-by: Satyam Sharma <satyam@infradead.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>