Merge #16634: doc: Refer in rpcbind doc to the manpage

fa0119a doc: Refer in rpcbind doc to the manpage (MarcoFalke)

Pull request description:

  The help was outdated, so refer to the updated manpage instead.

  * closes #14740
  * closes #9272

ACKs for top commit:
  emilengler:
    Concept ACK fa0119a
  laanwj:
    ACK fa0119a
  fanquake:
    ACK fa0119a

Tree-SHA512: 9836e4f31ece7acae334b47e3104b4595d0d1c1977af386a9463faf49aea9de3ab1c1dc3de248d0ee09e3b13693eaf6902dc82d277062e1bb1980b1117236fbb

Author: laanwj

share/examples/bitcoin.conf

@@ -70,8 +70,8 @@
 # server=1 tells Bitcoin-Qt and bitcoind to accept JSON-RPC commands
 #server=0
 
-# Bind to given address to listen for JSON-RPC connections. Use [host]:port notation for IPv6.
-# This option can be specified multiple times (default: bind to all interfaces)
+# Bind to given address to listen for JSON-RPC connections.
+# Refer to the manpage or bitcoind -help for further details.
 #rpcbind=<addr>
 
 # If no rpcpassword is set, rpc cookie auth is sought. The default `-rpccookiefile` name