target/riscv: optimize indirect branches

Signed-off-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

target/riscv/translate.c

@@ -548,7 +548,7 @@ static void gen_jalr(CPURISCVState *env, DisasContext *ctx, uint32_t opc,
         if (rd != 0) {
             tcg_gen_movi_tl(cpu_gpr[rd], ctx->pc_succ_insn);
         }
-        tcg_gen_exit_tb(NULL, 0);
+        tcg_gen_lookup_and_goto_ptr();
 
         if (misaligned) {
             gen_set_label(misaligned);