target/s390x: Use insn_start from DisasContextBase

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

target/s390x/tcg/translate.c

@@ -141,7 +141,6 @@ struct DisasFields {
 struct DisasContext {
     DisasContextBase base;
     const DisasInsn *insn;
-    TCGOp *insn_start;
     DisasFields fields;
     uint64_t ex_value;
     /*
@@ -6314,7 +6313,7 @@ static DisasJumpType translate_one(CPUS390XState *env, DisasContext *s)
     insn = extract_insn(env, s);
 
     /* Update insn_start now that we know the ILEN.  */
-    tcg_set_insn_start_param(s->insn_start, 2, s->ilen);
+    tcg_set_insn_start_param(s->base.insn_start, 2, s->ilen);
 
     /* Not found means unimplemented/illegal opcode.  */
     if (insn == NULL) {
@@ -6468,7 +6467,6 @@ static void s390x_tr_insn_start(DisasContextBase *dcbase, CPUState *cs)
 
     /* Delay the set of ilen until we've read the insn. */
     tcg_gen_insn_start(dc->base.pc_next, dc->cc_op, 0);
-    dc->insn_start = tcg_last_op();
 }
 
 static target_ulong get_next_pc(CPUS390XState *env, DisasContext *s,