prevent attempts to modify `secp256k1_context_no_precomp`
prevent attempts to modify `secp256k1_context_no_precomp`

libbitcoin/secp256k1,evoskuil/secp256k1,afk11/secp256k1,bitcoin-core/secp256k1,pmienk/secp256k1,evoskuil/secp256k1,peterdettman/secp256k1,afk11/secp256k1,bitcoin/secp256k1,evoskuil/secp256k1,pmienk/secp256k1,bitcoin/secp256k1,bitcoin/secp256k1,libbitcoin/secp256k1,bitcoin/secp256k1,pmienk/secp256k1,peterdettman/secp256k1,libbitcoin/secp256k1,evoskuil/secp256k1,libbitcoin/secp256k1,evoskuil/secp256k1,pmienk/secp256k1,ElementsProject/secp256k1-zkp,afk11/secp256k1,libbitcoin/secp256k1,bitcoin-core/secp256k1,pmienk/secp256k1,ElementsProject/secp256k1-zkp,afk11/secp256k1,afk11/secp256k1,bitcoin/secp256k1