fix bug in reshape: (#20781)

consider the situation that shape of input can contain more than one -1.
test=develop

paddle/fluid/operators/reshape_op.cc

@@ -186,14 +186,17 @@ class ReshapeOp : public framework::OperatorWithKernel {
         output_shape[unk_dim_idx] = -1;
       }
     } else {
+      if (all_positive) {
         PADDLE_ENFORCE_EQ(
             capacity, in_size,
             "ShapeError: The 'shape' in ReshapeOp is invalid. "
             "The input tensor X'size must be equal to the capacity of 'shape'. "
-          "But received X's shape = [%s], X's size = %d, 'shape' is [%s], the "
+            "But received X's shape = [%s], X's size = %d, 'shape' is [%s], "
+            "the "
             "capacity of 'shape' is %d.",
             in_dims, in_size, framework::make_ddim(shape), capacity);
       }
+    }
     return framework::make_ddim(output_shape);
   }