x86: fix style errors in nmi_int.c

This patch fixes most errors detected by checkpatch.pl.

                                     errors   lines of code   errors/KLOC
arch/x86/oprofile/nmi_int.c (after)       1             461           2.1
arch/x86/oprofile/nmi_int.c (before)     60             477         125.7

No code changed.

size:
   text    data     bss     dec     hex filename
   2675     264     472    3411     d53 nmi_int.o.after
   2675     264     472    3411     d53 nmi_int.o.before

md5sum:
  847aea0cc68fe1a2b5e7019439f3b4dd  nmi_int.o.after
  847aea0cc68fe1a2b5e7019439f3b4dd  nmi_int.o.before

Signed-off-by: Carlos R. Mafra <crmafra@gmail.com>
Reviewed-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>