tcg/optimize: Use fold_xx_to_i for orc

Recognize the constant function for or-complement.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

tcg/optimize.c

@@ -1586,6 +1586,7 @@ static bool fold_or(OptContext *ctx, TCGOp *op)
 static bool fold_orc(OptContext *ctx, TCGOp *op)
 {
     if (fold_const2(ctx, op) ||
+        fold_xx_to_i(ctx, op, -1) ||
         fold_xi_to_x(ctx, op, -1) ||
         fold_ix_to_not(ctx, op, 0)) {
         return true;