Omit xmlish(profasm,profc) for the 6.8 branch

testsuite/tests/ghc-regress/lib/Generics/xmlish/test.T

 setTestOpts(only_compiler_types(['ghc']))
 
 test( 'xmlish',
-      skip_if_fast,
+      compose(skip_if_fast,
+              # These are pretty consistent about giving
+              #     magic number mismatch: old/corrupt interface file?
+              # when run after the other ways.
+              if_compiler_lt('ghc', '6.9', omit_ways(['profasm', 'profc']))),
       multimod_compile_and_run,
       ['Main','']
     )