[MIPS] Fix gcc 3.3 warning.

  CC      arch/mips/kernel/cpu-bugs64.o
arch/mips/kernel/cpu-bugs64.c: In function 'align_mod':
arch/mips/kernel/cpu-bugs64.c:23: warning: asm operand 0 probably doesn't match constraints
arch/mips/kernel/cpu-bugs64.c:23: warning: asm operand 1 probably doesn't match constraints

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>