Merging Two elements with same name using xslt

Hi am having an xml like this

 <root>
<order>
<ordernumber>123</ordernumber>
</order>
<order>
<ordername>abc</ordername>
</order>
</root>

I need the output like below

 <root>
<order>
<ordernumber>123</ordernumber>
<ordername>abc</ordername>
</order>
</root>