Fix CTFE Error: reinterpreting cast from inout(string)*

std/typecons.d(648): Error: reinterpreting cast from inout(string)* to inout(Tuple!(string, string, string))* is not supported in CTFE
std/traits.d(566):        called from here: findSplit(s, "(").asTuple._Tuple_super()
std/traits.d(568):        called from here: adjustIdent("std")
std/traits.d(556): Error: template instance std.traits.fqnSym!(std) error instantiating
std/traits.d(556):        instantiated from here: fqnSym!(traits)
std/traits.d(478):        instantiated from here: fqnSym!(fullyQualifiedName)
std/traits.d(484):        instantiated from here: fullyQualifiedName!(fullyQualifiedName)
std/traits.d(484):        while evaluating: static assert(fullyQualifiedName!(fullyQualifiedName) == "std.traits.fullyQualifiedName")

std/traits.d

@@ -563,7 +563,7 @@ private template fqnSym(alias T)
 
         if (s.skipOver("package ") || s.skipOver("module "))
             return s;
-        return s.findSplit("(")[0];
+        return s.findSplit("(").pre;
     }
     enum fqnSym = parentPrefix ~ adjustIdent(__traits(identifier, T));
 }