[Feat] (DirectVulkan): run the tessellation stages

The backend already turned a tessellation control/evaluation shader into the
right VkShaderStage, but nothing downstream knew what to do with it: GL_PATCHES
had no topology, so it fell through to the triangle-list default, and the
pipeline carried no tessellation state at all. A GL_PATCHES draw therefore ran
the vertex and fragment stages over raw triangles.

Map GL_PATCHES to VK_PRIMITIVE_TOPOLOGY_PATCH_LIST, carry GL_PATCH_VERTICES into
the pipeline as patchControlPoints (part of the key, since two patch sizes are
two pipelines), attach VkPipelineTessellationStateCreateInfo for a patch topology
only, and enable the tessellationShader device feature.

POST reports the feature, because without it a program with a tessellation stage
cannot build a pipeline at all and GL_PATCHES draws render nothing.

MobileGL/MG_Util/Converters/MGToVk/RenderStateEnumConverter.cpp

@@ -38,6 +38,10 @@ namespace MobileGL {
                 return VK_PRIMITIVE_TOPOLOGY_TRIANGLE_LIST_WITH_ADJACENCY;
             case GL_TRIANGLE_STRIP_ADJACENCY:
                 return VK_PRIMITIVE_TOPOLOGY_TRIANGLE_STRIP_WITH_ADJACENCY;
+            case GL_PATCHES:
+                // The tessellator decides what a patch becomes; its vertex count is pipeline
+                // state (patchControlPoints), not part of the topology.
+                return VK_PRIMITIVE_TOPOLOGY_PATCH_LIST;
             default:
                 MGLOG_W("Unrecognized primitive topology");
                 return VK_PRIMITIVE_TOPOLOGY_TRIANGLE_LIST;