Previously, some useful xrefs were missing.
Now each of the pages refers to all remaining section 2 pages,
to the kld(4) page, and to a related utility's (section 8) page.
change the name of the page (.Nm) from "kldstat" to "modstat".
Second, don't claim that modstat(2) always returns 0. Actually,
it behaves as most syscalls do - returns 0 on success, or -1
on failure.
MFC after: 5 days
