riscv: Make NUMA depend on MMU

NUMA is useless when NOMMU, and it leads some build error,
make it depend on MMU.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
1 file changed