Fix ADM_register_pfs_storage, ADM_remove_pfs_storage and ADM_update_pfs_storage

The following error occurs with all three when implementing the test for each of them:

FATAL: ADM_register_pfs_storage() failed: Unknown remote procedure: ADM_register_pfs_storage
FATAL: ADM_remove_pfs_storage() failed: Unknown remote procedure: ADM_remove_pfs_storage
FATAL: ADM_update_pfs_storage() failed: Unknown remote procedure: ADM_update_pfs_storage

Server does not receive the rpcs as they do not appear there when executing ctest.