bitcoin-spv - unnecessary intermediate cast
`CheckBitcoinSigs.accountFromPubkey()` casts the `bytes32` keccack256 hash of the `pubkey` to `uint256`, then `uint160` and then finally to `address` while the intermediate cast is not required.\\n```\\n/// @notice Derives an Ethereum Account address from a pubkey\\n/// @dev The address is the last 20 bytes of the keccak256 of the address\\n/// @param \\_pubkey The public key X & Y. Unprefixed, as a 64-byte array\\n/// @return The account address\\nfunction accountFromPubkey(bytes memory \\_pubkey) internal pure returns (address) {\\n    require(\\_pubkey.length == 64, "Pubkey must be 64-byte raw, uncompressed key.");\\n\\n    // keccak hash of uncompressed unprefixed pubkey\\n    bytes32 \\_digest = keccak256(\\_pubkey);\\n    return address(uint160(uint256(\\_digest)));\\n}\\n```\\n
The intermediate cast from `uint256` to `uint160` can be omitted. Refactor to `return address(uint256(_digest))` instead.
```\\n/// @notice Derives an Ethereum Account address from a pubkey\\n/// @dev The address is the last 20 bytes of the keccak256 of the address\\n/// @param \\_pubkey The public key X & Y. Unprefixed, as a 64-byte array\\n/// @return The account address\\nfunction accountFromPubkey(bytes memory \\_pubkey) internal pure returns (address) {\\n    require(\\_pubkey.length == 64, "Pubkey must be 64-byte raw, uncompressed key.");\\n\\n    // keccak hash of uncompressed unprefixed pubkey\\n    bytes32 \\_digest = keccak256(\\_pubkey);\\n    return address(uint160(uint256(\\_digest)));\\n}\\n```\\n