glsl: TCS outputs can not be transform feedback candidates on GLES
Avoids regression on: KHR-GLES*.core.tessellation_shader.single.xfb_captures_data_from_correct_stage that is uncovered by the following patch. "glsl: fix recording of variables for XFB in TCS shaders" v2: Rebased over glsl: fix recording of variables for XFB in TCS shaders v3: Move this patch before "glsl: fix recording of variables for XFB in TCS shaders" to avoid temporal regressions. (Illia Mirkin) Cc: 19.0 <mesa-stable@lists.freedesktop.org> Reviewed-by:Timothy Arceri <tarceri@itsqueeze.com> (cherry picked from commit bf1f4948)