and tweak lkminit_*.c (where applicable) to call them, and to call
sysctl_teardown() when being unloaded.
This consists of (1) making setup functions not be static when being
compiled as lkms (change to sys/sysctl.h), (2) making prototypes
visible for the various setup functions in header files (changes to
various header files), and (3) making simple "load" and "unload"
functions in the actual lkminit stuff.
linux_sysctl.c also needs its root exposed (ie, made not static) for
this (when built as an lkm).
server supports it
for this, need NT CREATE AND X a directory in smbfs_open(), so that
we get the FID handle used for DIRECTORY CHANGE NOTIFY SMB
this could eventually be used to 'watch' even regular files, by
watching its parent directory and lookup/VN_KNOTE() when we get
REMOVED/RENAMED/MODIFIED action
also reorganize the kqueue code somewhat to use simplify locking
and knote detach