Cycles: Repot CPU and CUDA capabilities to system info operator

For CPU it gives available instructions set (SSE, AVX and so).

For GPU CUDA it reports most of the attribute values returned by
cuDeviceGetAttribute(). Ideally we need to only use set of those
which are driver-specific (so we don't clutter system info with
values which we can get from GPU specifications and be sure they
stay the same because driver can't affect on them).

intern/cycles/device/device_opencl.cpp

@@ -1195,7 +1195,12 @@ void device_opencl_info(vector<DeviceInfo>& devices)
 	}
 }
 
+string device_opencl_capabilities(void)
+{
+	/* TODO(sergey): Not implemented yet. */
+	return "";
+}
+
 CCL_NAMESPACE_END
 
 #endif /* WITH_OPENCL */
-