target-alpha: Use non-local temps for zero/sink

These values are no longer live across branches.

Signed-off-by: Richard Henderson <rth@twiddle.net>

target-alpha/translate.c

@@ -153,15 +153,15 @@ void alpha_translate_init(void)
 static TCGv load_zero(DisasContext *ctx)
 {
     if (TCGV_IS_UNUSED_I64(ctx->zero)) {
-        ctx->zero = tcg_const_local_i64(0);
+        ctx->zero = tcg_const_i64(0);
     }
     return ctx->zero;
 }
 
 static TCGv dest_sink(DisasContext *ctx)
 {
     if (TCGV_IS_UNUSED_I64(ctx->sink)) {
-        ctx->sink = tcg_temp_local_new();
+        ctx->sink = tcg_temp_new();
     }
     return ctx->sink;
 }