win32: Pretend that close-on-exec works

Currently virNetSocketNew fails because virSetCloseExec fails as there
is no proper implementation for it on Windows at the moment. Workaround
this by pretending that setting close-on-exec on the fd works. This can
be done because libvirt currently lacks the ability to create child
processes on Windows anyway. So there is no point in failing to set a
flag that isn't useful at the moment anyway.

src/util/util.c

@@ -275,7 +275,11 @@ int virSetInherit(int fd, bool inherit) {
 
 int virSetInherit(int fd ATTRIBUTE_UNUSED, bool inherit ATTRIBUTE_UNUSED)
 {
-    return -1;
+    /* FIXME: Currently creating child processes is not supported on
+     * Win32, so there is no point in failing calls that are only relevant
+     * when creating child processes. So just pretend that we changed the
+     * inheritance property of the given fd as requested. */
+    return 0;
 }
 
 #endif /* WIN32 */