x86: coding style fixes to arch/x86/kernel/cpu/nexgen.c

arch/x86/kernel/cpu/nexgen.o:
   text    data     bss     dec     hex filename
    111     316       0     427     1ab nexgen.o.before
    111     316       0     427     1ab nexgen.o.after
md5:
 e796efefea9ebc6644338bad226599ee  nexgen.o.before.asm
 e796efefea9ebc6644338bad226599ee  nexgen.o.after.asm

Signed-off-by: Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>