this is the exact procedure that i have done and it worked for me:
1- rename svm
2- create a new svm with correct configuration
3- delete snapmirror from old svm (without snapmirror break command so the configuration of snapmirror can be retained)
4- rehost the volume to a new created svm
5- create snapmirror relationship on the new SVM
6- trigger snapmirror update