drvfail006 and drvfail008 need mtl

testsuite/tests/ghc-regress/deriving/should_fail/all.T

@@ -4,9 +4,9 @@ test('drvfail002', normal, compile_fail, [''])
 test('drvfail003', normal, compile_fail, [''])
 test('drvfail004', normal, compile_fail, [''])
 test('drvfail005', normal, compile_fail, [''])
-test('drvfail006', normal, compile_fail, [''])
+test('drvfail006', reqlib('mtl'), compile_fail, [''])
 test('drvfail007', normal, compile_fail, [''])
-test('drvfail008', normal, compile_fail, [''])
+test('drvfail008', reqlib('mtl'), compile_fail, [''])
 test('drvfail009', normal, compile_fail, [''])
 test('drvfail010', normal, compile_fail, [''])
 test('drvfail011', normal, compile_fail, [''])