Add VaList::empty

Author: lucic71

libcc2rs/src/va_args.rs

@@ -51,6 +51,10 @@ pub struct VaList<'a> {
 }
 
 impl<'a> VaList<'a> {
+    pub fn empty() -> Self {
+        VaList { args: &[], pos: 0 }
+    }
+
     pub fn new(args: &'a [VaArg]) -> Self {
         VaList { args, pos: 0 }
     }