removing `_t` from secp256k1 classes (POSIX reserved per https://github.com/bitcoin/secp256k1/commit/dd891e0ed5e19603bd6618729db1e4513600a87b)
removing `_t` from secp256k1 classes (POSIX reserved per https://github.com/bitcoin/secp256k1/commit/dd891e0ed5e19603bd6618729db1e4513600a87b)

Blockstream/contracthashtool,Blockstream/contracthashtool