netfilter: bitwise: improve error goto labels

Replace two labels (`err1` and `err2`) with more informative ones.

Signed-off-by: Jeremy Sowden <[e-mail]>
Signed-off-by: Florian Westphal <[e-mail]>

net/netfilter/nft_bitwise.c

···
 		return err;
 	if (mask.type != NFT_DATA_VALUE || mask.len != priv->len) {
 		err = -EINVAL;
-		goto err1;
+		goto err_mask_release;
 	}
 
 	err = nft_data_init(NULL, &priv->xor, sizeof(priv->xor), &xor,
 			    tb[NFTA_BITWISE_XOR]);
 	if (err < 0)
-		goto err1;
+		goto err_mask_release;
 	if (xor.type != NFT_DATA_VALUE || xor.len != priv->len) {
 		err = -EINVAL;
-		goto err2;
+		goto err_xor_release;
 	}
 
 	return 0;
-err2:
+
+err_xor_release:
 	nft_data_release(&priv->xor, xor.type);
-err1:
+err_mask_release:
 	nft_data_release(&priv->mask, mask.type);
 	return err;
 }