daemon: Fix the wrong macro name

WITH_INTERFACE is not defined, it should be WITH_NETCF there to load
the interface driver.

Eric posted patch weeks ago to resolve the problems in the whole
build system, but it's not finalised yet:

https://www.redhat.com/archives/libvir-list/2012-June/msg01299.html

I'm going to simply fix the wrong macro name here so that the
interface driver could loaded, and continue the work on the listing
API for interface driver.

daemon/libvirtd.c

@@ -378,7 +378,7 @@ static void daemonInitialize(void)
 # ifdef WITH_NWFILTER
     virDriverLoadModule("nwfilter");
 # endif
-# ifdef WITH_INTERFACE
+# ifdef WITH_NETCF
     virDriverLoadModule("interface");
 # endif
 # ifdef WITH_QEMU

tests/virdrivermoduletest.c

@@ -79,7 +79,7 @@ mymain(void)
 #ifdef WITH_NWFILTER
     TEST("nwfilter", NULL);
 #endif
-#ifdef WITH_INTERFACE
+#ifdef WITH_NETCF
     TEST("interface", NULL);
 #endif
 #ifdef WITH_QEMU