ae0ba6c135 Take spent closure by value in count_witness_sigops and count_p2sh_sigops (jrakibi)
Pull request description:
This fixes#4141
Changed `count_witness_sigops` to take the `spent` closure by value instead of `&mut`
This removes the need for `&mut` when calling the function while still allowing mutable closure to be passed when needed
ACKs for top commit:
Kixunil:
ACK ae0ba6c135
tcharding:
ACK ae0ba6c135
apoelstra:
ACK ae0ba6c1356505697fc5e841741ac488538e3407; successfully ran local tests
Tree-SHA512: 76c5c98994b00412d0d371c07e3e83538f21754129a67889c66e1299e0453defaecb82bd4305297f772d65b042045d3579eaac14f8ea59419bf26b8b0d2ac84f