implement -no-user-config command-line option (v3)

Changes v2 -> v3:
 - Rebase against latest qemu.git

Changes v1 -> v2:
 - Change 'userconfig' field/variables to bool instead of int
 - Coding style change

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/qemu-config.h b/qemu-config.h
index ff934a1..6d7365d 100644
--- a/qemu-config.h
+++ b/qemu-config.h
@@ -18,6 +18,6 @@
 
 /* Read default Qemu config files
  */
-int qemu_read_default_config_files(void);
+int qemu_read_default_config_files(bool userconfig);
 
 #endif /* QEMU_CONFIG_H */