test: xfail-fast the cci tests

Author: brson

src/test/run-pass/cci_iter_exe.rs

@@ -1,3 +1,4 @@
+// xfail-fast - check-fast doesn't understand aux-build
 // aux-build:cci_iter_lib.rs
 
 use std;

src/test/run-pass/cci_no_inline_exe.rs

@@ -1,3 +1,4 @@
+// xfail-fast - check-fast doesn't understand aux-build
 // aux-build:cci_no_inline_lib.rs
 
 use std;