Merge bitcoin/bitcoin#22837: doc: mention bech32m/BIP350 in doc/descriptors.md

d2a09c8 doc: mention bech32m/BIP350 in doc/descriptors.md (Pieter Wuille)

Pull request description:

  As it says on the tin.

ACKs for top commit:
  0xB10C:
    ACK d2a09c8
  fanquake:
    ACK d2a09c8 - can be backported for coherent documentation. Bech32m support was backported into branches back to the 0.19.

Tree-SHA512: a75d8bbf1ab062ec19e14cbe38dd0405a08c58e5dd4e9d94881f2c5efd52cc22dc755eae8d21bbda066feb099d93312b65557900bc2e65a70ba0412614cf0135

Author: fanquake

doc/descriptors.md

@@ -99,7 +99,7 @@ Descriptors consist of several types of expressions. The top level expression is
 `ADDR` expressions are any type of supported address:
 - P2PKH addresses (base58, of the form `1...` for mainnet or `[nm]...` for testnet). Note that P2PKH addresses in descriptors cannot be used for P2PK outputs (use the `pk` function instead).
 - P2SH addresses (base58, of the form `3...` for mainnet or `2...` for testnet, defined in [BIP 13](https://github.com/bitcoin/bips/blob/master/bip-0013.mediawiki)).
-- Segwit addresses (bech32, of the form `bc1...` for mainnet or `tb1...` for testnet, defined in [BIP 173](https://github.com/bitcoin/bips/blob/master/bip-0173.mediawiki)).
+- Segwit addresses (bech32 and bech32m, of the form `bc1...` for mainnet or `tb1...` for testnet, defined in [BIP 173](https://github.com/bitcoin/bips/blob/master/bip-0173.mediawiki) and [BIP 350](https://github.com/bitcoin/bips/blob/master/bip-0350.mediawiki)).
 
 ## Explanation