Move defered Unlock() before a possible function return.
Move defered Unlock() before a possible function return.

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