target/riscv: rvk: add support for zbkb extension

- reuse partial instructions of zbb extension, update extension check for them
 - add brev8, pack, packh, packw, unzip, zip instructions

Signed-off-by: Weiwei Li <liweiwei@iscas.ac.cn>
Signed-off-by: Junqiang Wang <wangjunqiang@iscas.ac.cn>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220423023510.30794-3-liweiwei@iscas.ac.cn>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

target/riscv/translate.c

@@ -688,6 +688,13 @@ EX_SH(12)
     }                                  \
 } while (0)
 
+#define REQUIRE_EITHER_EXT(ctx, A, B) do {       \
+    if (!ctx->cfg_ptr->ext_##A &&      \
+        !ctx->cfg_ptr->ext_##B) {      \
+        return false;                            \
+    }                                            \
+} while (0)
+
 static int ex_rvc_register(DisasContext *ctx, int reg)
 {
     return 8 + reg;