virnetdev: Use ifname in virNetDevGetLinkInfo

If we're compiling on non-Linux platform, the virNetDevGetLinkInfo()
is a dummy function which barely logs debug message that getting link
info is not supported. However, while the debug message was prepared
for printing the interface name too, I actually forgot to pass the
variable which resulted in build error on platforms like mingw or
FreeBSD.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

src/util/virnetdev.c

@@ -1921,7 +1921,8 @@ virNetDevGetLinkInfo(const char *ifname,
                      virInterfaceLinkPtr lnk)
 {
     /* Port me */
-    VIR_DEBUG("Getting link info on %s is not implemented on this platform");
+    VIR_DEBUG("Getting link info on %s is not implemented on this platform",
+              ifname);
     lnk->speed = lnk->state = 0;
     return 0;
 }