proxy: fix wildcard address use

proxy: fix wildcard address use

This patch fixes a regression for hosts disabling ipv6 via kernel
commandline ('ipv6.disable=1')introduced in commit
e224b7d2e6a729b48e9669e200fd7aeb1e9b5702
(disabling IPv6 via sysctl did not exhibit these problems)

by hardcoding the address to '::', pveproxy and spiceproxy failed to
start with:
'unable to create socket - Address family not supported by protocol'

This patch depends on the commit in pve-common, which tries first
binding to '::' and then falling back to '0.0.0.0', and needs a
versioned dependency bump on libpve-common-perl.

With this patch the listening addresses are (`ss -tlnp |grep 8006` output)
* ipv6 disabled via kernel cmdline: '0.0.0.0:8006'
* sysctl net.ipv6.conf.all.disable_ipv6=1: '*:8006'
* sysctl net.ipv6.bindv6only=1: '[::]:8006'
* else: '*:8006'

Signed-off-by: Stoiko Ivanov <s.ivanov@proxmox.com>