Assuming you have used client side controls only , there is no need to do anything special such as deployment of telerik dlls on server. Once you have the XAP file , the Telerik dlls should be already present inside the XAP file and this should be enough.
As a side note - you may easily check whether the dlls are present in the XAP file by opening it ( as you know this is a regular zip file with changed extension ) .
* Since you are at the deployment stage I believe this article may be of interest to you as well
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