[g5k-pmem-manager] use the ref-api to determine if the node has pmem
Fixes bug #12809, it's safe to use the reference-api in place of use ipmctl. Indeed, ipmctl is taken from backports and doesn't have stable outputs and error codes.
Fixes bug #12809, it's safe to use the reference-api in place of use ipmctl. Indeed, ipmctl is taken from backports and doesn't have stable outputs and error codes.