f5412e2aa2 Fix clippy warnings (Tobin C. Harding)
Pull request description:
Clippy recently upgraded and a few two new warnings types popped up in our codebase, fix them both in a single patch so CI passes for all commits.
1. Remove unneeded explicit borrow
2. Use `if let Some` instead of pattern match
ACKs for top commit:
apoelstra:
ACK f5412e2aa2
Kixunil:
ACK f5412e2aa2
Tree-SHA512: 1faeb6173061e28a1acfe1a37a669982abbd832b327448e31648c447a7d043841edf30349700ff9da9dd330cfa6d497d188534daab825069e4489653e25987ca