Generalise RPC connection handling code to allow more listening sockets
Generalise RPC connection handling code to allow more listening sockets

Using this modification it should be relatively easy to, at a later
time, listen on multiple addresses (even Unix domain sockets should be
possible).

Signed-off-by: Giel van Schijndel <b1c1d8736f20db3fb6c1c66bb1455ed43909f0d8@mortis.eu>

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