x86: remove arch/x86/kernel/smpcommon_32.c

Yinghai Lu noticed that arch/x86/kernel/smpcommon_32.c got
renamed to arch/x86/kernel/smpcommon.c but the old almost-empty
file stayed around. Zap it.

Reported-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>