testsuite: T13786 does not appear broken on linux with non-dynamic.

The referenced issue 20706 also doesn't list T13786 as a broken test.

Author: angerman

testsuite/tests/ghci/T13786/all.T

@@ -1,4 +1,4 @@
 test('T13786',
-     [when(unregisterised(), fragile(17018)), req_c, when(opsys('linux') and not ghc_dynamic(), expect_broken(20706))],
+     [when(unregisterised(), fragile(17018)), req_c],
      makefile_test, [])
 

testsuite/tests/package/T20010/all.T

@@ -1,4 +1,10 @@
 # Test that GHC links to the C++ standard library as expected
 # when the system-cxx-std-lib package is used.
 test('T20010', req_c, makefile_test, [])
-test('T20010-ghci', [req_c, extra_files(['T20010_c.cpp', 'T20010.hs']), unless(ghc_dynamic(), expect_broken(20706))], makefile_test, [])
+test('T20010-ghci', [req_c, extra_files(['T20010_c.cpp', 'T20010.hs']),
+                     # this test is broken for dynamic builds.  However, windows
+                     # is dynamic, but not really, and works significanlty
+                     # different from linux and darwin to not be broken when
+                     # ghc claims to be dynamic.
+                     unless(ghc_dynamic() and not opsys('mingw32'), expect_broken(20706))],
+     makefile_test, [])