contrib: Use -daemonwait in systemd init script

Closes #21322 by making bitcoind conform to behavior specified for
`type=forking`.

Author: laanwj

contrib/init/bitcoind.service

@@ -18,7 +18,7 @@ After=network-online.target
 Wants=network-online.target
 
 [Service]
-ExecStart=/usr/bin/bitcoind -daemon \
+ExecStart=/usr/bin/bitcoind -daemonwait \
                             -pid=/run/bitcoind/bitcoind.pid \
                             -conf=/etc/bitcoin/bitcoin.conf \
                             -datadir=/var/lib/bitcoind
@@ -33,6 +33,7 @@ ExecStartPre=/bin/chgrp bitcoin /etc/bitcoin
 Type=forking
 PIDFile=/run/bitcoind/bitcoind.pid
 Restart=on-failure
+TimeoutStartSec=infinity
 TimeoutStopSec=600
 
 # Directory creation and permissions