TEST: Remove odd test in rendermode tests.

This specific test checked whether the pointer for two static strings have a
different address. Since the specific strings checked had the same "value"
string pooling optimizations will result in them to have the same address and
thus make this test fail. Furthermore, the test seemed completely pointless,
I simply dropped it now.

test/common/rendermode.h

@@ -49,7 +49,6 @@ class RenderModeTestSuite : public CxxTest::TestSuite {
 		 * Notably, the output should not be in mixed case.
 		 */
 		TS_ASSERT_SAME_DATA(Common::getRenderModeCode(Common::parseRenderMode("FMTOWNS")), "fmtowns", 7);
-		TS_ASSERT_DIFFERS(Common::getRenderModeCode(Common::parseRenderMode("FMTOWNS")), "fmtowns");
 		TS_ASSERT_SAME_DATA(Common::getRenderModeCode(Common::parseRenderMode("CGA")), "cga", 3);
 		TS_ASSERT_SAME_DATA(Common::getRenderModeCode(Common::parseRenderMode("vga")), "vga", 3);
 		TS_ASSERT_SAME_DATA(Common::getRenderModeCode(Common::parseRenderMode("Ega")), "ega", 3);