x86: fix printout ugliness in cpu info printk

fix print_cpu_info, because it produced on boot:

  CPU: <6>AMD Athlon(tm) 64 Processor 3200+ stepping 00

instead of:

  CPU: AMD Athlon(tm) 64 Processor 3200+ stepping 00

(broken since 04e1ba85

 -
 x86: cleanup kernel/setup_64.c)

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>