Remove unneeded return statement

New clipply lint in rustc nightly "unneeded `return` statement".

Remove it.

bitcoin/src/blockdata/transaction.rs

@@ -517,11 +517,11 @@ impl TransactionExtPriv for Transaction {
                 1
             } else if witness_program.is_p2wsh() {
                 // Treat the last item of the witness as the witnessScript
-                return witness
+                witness
                     .last()
                     .map(Script::from_bytes)
                     .map(|s| s.count_sigops())
-                    .unwrap_or(0);
+                    .unwrap_or(0)
             } else {
                 0
             }