remote: Don't attempt remote connection from libvirtd
remote: Don't attempt remote connection from libvirtd

When a hypervisor driver is not compiled in and a user enables the
monolithic libvirtd, they get the following misleading error:

  $ virsh -c qemu:///system
  error: failed to connect to the hypervisor
  error: Failed to connect socket to '/var/run/libvirt/virtqemud-sock': No such file or directory

The issue is that the daemon side of the remote driver can't find the
appropriate driver, but the remote driver always accepts everything and
thus attempts to delegate further, which in case of libvirtd makes no
sense.

Refuse opening a connection for local URIS even when the requested
driver is not registered in case when we are inside 'libvirtd' as
libvirtd doesn't have anything to delegate to.

  $ virsh -c qemu:///system
  error: failed to connect to the hypervisor
  error: no connection driver available for qemu:///system

Discovered when investigating https://gitlab.com/libvirt/libvirt/-/issues/370

Signed-off-by: Peter Krempa <2cf5c04c61aa466e4a47bfedc747d17279c72ffc@redhat.com>
Reviewed-by: Ján Tomko <4cab11cfb98d3c937327354a78eb07dbb6ee2bc6@redhat.com>

zippy2/libvirt,libvirt/libvirt,zippy2/libvirt,olafhering/libvirt,jfehlig/libvirt,jfehlig/libvirt,zippy2/libvirt,zippy2/libvirt,jfehlig/libvirt,libvirt/libvirt,jfehlig/libvirt,libvirt/libvirt,libvirt/libvirt,olafhering/libvirt,olafhering/libvirt,olafhering/libvirt