btcec is changed, this fixes btcwallet to work with the new changes.
btcec is changed, this fixes btcwallet to work with the new changes.

synrg-labs/btcwallet,jrick/btcwallet,btcsuite/btcwallet,btcsuite/btcwallet,decred/dcrwallet,synrg-labs/btcwallet,Stash-Crypto/btcwallet,Roasbeef/btcwallet,jrick/btcwallet,decred/dcrwallet,Roasbeef/btcwallet,jrick/dcrwallet,Stash-Crypto/btcwallet,jrick/dcrwallet