camera2 docs: Fix instructions for using SurfaceView.

     *

     * <ul>

     *

     * <li>For drawing to a {@link android.view.SurfaceView SurfaceView}: Set the size of the

     *   Surface with {@link android.view.SurfaceHolder#setFixedSize} to be one of the sizes

     *   returned by

     *   {@link StreamConfigurationMap#getOutputSizes(Class) getOutputSizes(SurfaceView.class)}

     * <li>For drawing to a {@link android.view.SurfaceView SurfaceView}: Once the SurfaceView's

     *   Surface is {@link android.view.SurfaceHolder.Callback#surfaceCreated created}, set the

     *   size of the Surface with {@link android.view.SurfaceHolder#setFixedSize} to be one of the

     *   sizes returned by

     *   {@link StreamConfigurationMap#getOutputSizes(Class) getOutputSizes(SurfaceHolder.class)}

     *   and then obtain the Surface by calling {@link android.view.SurfaceHolder#getSurface}.</li>

     *

     * <li>For accessing through an OpenGL texture via a