Avoid errors importing duplicate scripts when locked.
Avoid errors importing duplicate scripts when locked.

This reverses the checks for whether to return an error code for
duplicate scripts or a locked address manager so that the duplicate
check is performed first.  This prevents logging errors for duplicate
script imports even when the wallet is locked.

decred/dcrwallet,jrick/btcwallet,jrick/dcrwallet,jrick/btcwallet,decred/dcrwallet,jrick/dcrwallet