Like commit 1149aad1 ("arm64: Add dump_backtrace() in show_regs"),
dump the stack in riscv show_regs as common code expects.
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>