Move daemonize handling to OS specific files

Move daemonize handling from vl.c to OS specific files. Provide dummy
stubs for Win32.

Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Acked-by: Juan Quintela <quintela@redhat.com>
Acked-by: Richard Henderson <rth@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
diff --git a/qemu-os-posix.h b/qemu-os-posix.h
index 91c7b68..9b07660 100644
--- a/qemu-os-posix.h
+++ b/qemu-os-posix.h
@@ -33,5 +33,7 @@
 void os_setup_signal_handling(void);
 void os_change_process_uid(void);
 void os_change_root(void);
+void os_daemonize(void);
+void os_setup_post(void);
 
 #endif