i386: Remove local CPU logic in MTRR call to smp_call_function_single

smp_call_function_single handles the call to local CPU case correctly
now, no need to handle this in the caller.

[ tglx: arch/x86 adaptation ]

Signed-off-by: Andrew Morton <akpm@linux-foundation.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>