Store the added system info in the runSet's xml data structure if the storeSystemInfo method is called with a new host as parameter. This is necessary if the benchmark script is used together with the VCloud's webclient.

git-svn-id: https://svn.sosy-lab.org/software/cpachecker/trunk@14775 4712c6d2-40bb-43ae-aa4b-fec3f1bdfe4c