Starting from libvirt-1.2.4, network state XML files moved to another
directory (see commit b9e95491) and libvirt automatically migrates the
network state files to a new location. However, the code used
dirent.d_type which is not supported by all filesystems. Thus, when
libvirt was upgraded on a host which used such filesystem, network state
XMLs were not properly moved and running networks disappeared from
libvirt.

This patch falls back to lstat() whenever dirent.d_type is DT_UNKNOWN to
fix this issue.

https://bugzilla.redhat.com/show_bug.cgi?id=1167145


Signed-off-by: Jiri Denemark <jdenemar@redhat.com>