Figured it out already. Solution for those who are interested:
<animateTransform id="anim1" attributeName="transform" attributeType="XML" type="rotate" from="0" to="30" begin="0s; anim2.end" dur="0.4s" fill="freeze"/>
<animateTransform id="anim2" attributeName="transform" attributeType="XML" type="rotate" from="30" to="0" begin="anim1.end" dur="0.4s" fill="freeze"/>