Function normalize

Source/astcenc_vecmathlib.h:353–357

* @brief Normalize a non-zero length vector to unit length. */

 * @brief Normalize a non-zero length vector to unit length.
 */
static ASTCENC_SIMD_INLINE vfloat4 normalize(vfloat4 a)
{
	vfloat4 length = dot(a, a);
	return a / sqrt(length);
}

/**
 * @brief Normalize a vector, returning @c safe if len is zero.