gnu: c-reduce: Use llvm and clang 3.5.

* gnu/packages/debug.scm (c-reduce)[intputs]: Use llvm and clang 3.5.

gnu/packages/debug.scm

@@ -99,8 +99,8 @@ (define-public c-reduce
     (inputs
      `(("astyle"          ,astyle)
        ("delta"           ,delta)
-       ("llvm"            ,llvm)
-       ("clang"           ,clang)
+       ("llvm"            ,llvm-3.5)
+       ("clang"           ,clang-3.5)
        ("flex"            ,flex)
        ("indent"          ,indent)
        ("perl"            ,perl)