Measurement characteristics are allocated during channel path
registration but not freed during deregistration. Fix this by
embedding these characteristics inside struct channel_path.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>