Prospective fix for running cmake tests with -no-widgets

Don't try to run test_interface when Qt is configured without QtWidgets.

Change-Id: If6c376c250215c1d639b06881d16c0141091f288
Reviewed-by: Stephen Kelly <ske@ableton.com>

tests/auto/cmake/CMakeLists.txt

@@ -127,7 +127,7 @@ if (QT_WITH_ANGLE OR (NOT WIN32 AND NOT APPLE AND NOT NO_EGL))
 endif()
 expect_pass(test_opengl_lib)
 
-if (NOT CMAKE_VERSION VERSION_LESS 2.8.11)
+if (NOT CMAKE_VERSION VERSION_LESS 2.8.11 AND NOT NO_WIDGETS)
     expect_pass(test_interface)
 endif()