Do not expect TCS shader with XFB variables to fail linkging in GL

Do not expect TCS shader with XFB variables to fail linkging in GL

The test tries to link shader with XFB variables in TCS, without TES stage.
The test expects the shader to fail linking, but this behavior does not
seem to be mandated by GL spec.

According to GL 4.6 spec (
https://www.khronos.org/registry/OpenGL/specs/gl/glspec46.core.pdf - page 387)
- It is not forbidden to use TransformFeedbackVaryings with Tessellation Control
Shader and the spec does not mandate linking failure, even without NV_gpu_shader5
extension.

Test seems to derive this behavior from OGL ES spec where XFB is not allowed
within TCS shader.

Components: OpenGL

VK-GL-CTS Issue: 1221

Affects:
KHR-GL45.tessellation_shader.single.xfb_captures_data_from_correct_stage

Change-Id: Ie7c4209e0a36d48e56df04030ed095741bda155a