oops, xfail-fast the cross-crate superkind tests

src/test/compile-fail/builtin-superkinds-in-metadata.rs

@@ -8,6 +8,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+// xfail-fast
+
 // aux-build:trait_superkinds_in_metadata.rs
 
 // Test for traits inheriting from the builtin kinds cross-crate.

src/test/run-pass/builtin-superkinds-capabilities-xc.rs

@@ -8,6 +8,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+// xfail-fast
+
 // aux-build:trait_superkinds_in_metadata.rs
 
 // Tests "capabilities" granted by traits with super-builtin-kinds,

src/test/run-pass/builtin-superkinds-in-metadata.rs

@@ -8,6 +8,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+// xfail-fast
+
 // aux-build:trait_superkinds_in_metadata.rs
 
 // Tests (correct) usage of trait super-builtin-kinds cross-crate.