Fix bogus Name assignment in CreateStatistics
Apparently, it doesn't work to use a plain cstring as a Name datum: you
may end up having random bytes because of failing to zero the bytes
after the terminating 0,円 as indicated by valgrind. I introduced this
bug in
5564c1181548, so backpatch this fix to REL_10_STABLE, like that
commit.
While at it, fix a slightly misleading comment, pointed out by David
Rowley.