Add a test for trac #1588: unrequested generalized newtype deriving?

Test is drvfail013

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

@@ -11,3 +11,4 @@ test('drvfail009', normal, compile_fail, [''])
 test('drvfail010', normal, compile_fail, [''])
 test('drvfail011', normal, compile_fail, [''])
 test('drvfail012', normal, compile_fail, [''])
+test('drvfail013', normal, compile_fail, [''])

testsuite/tests/ghc-regress/deriving/should_fail/drvfail013.hs

+
+-- Test for trac #1588: unrequested generalized newtype deriving?
+
+newtype MaybeT  m a = MaybeT  { runMaybeT  :: m (Maybe a) } deriving Eq
+
+data    MaybeT' m a = MaybeT' { runMaybeT' :: m (Maybe a) } deriving Eq

testsuite/tests/ghc-regress/deriving/should_fail/drvfail013.stderr

+
+drvfail013.hs:4:0:
+    No instance for (Eq (m (Maybe a)))
+      arising from the 'deriving' clause of a data type declaration
+                   at drvfail013.hs:4:0-70
+    Possible fix: add an instance declaration for (Eq (m (Maybe a)))
+    When deriving the instance for (Eq (MaybeT m a))
+
+drvfail013.hs:6:0:
+    No instance for (Eq (m (Maybe a)))
+      arising from the 'deriving' clause of a data type declaration
+                   at drvfail013.hs:6:0-70
+    Possible fix: add an instance declaration for (Eq (m (Maybe a)))
+    When deriving the instance for (Eq (MaybeT' m a))