lsof won't build on -current

["Steven M. Bellovin" <smb%cs.columbia.edu@localhost>]

lsof won't compile on -current:

cc -O2  -DNETBSDV=3099000 -DHASGETBOOTFILE -DHASKVMGETPROC2 -DHASNFSPROTO -DHASI
Pv6 -DHASFDESCFS=1 -DHASFDLINK -DHASNULLFS -DHASPROCFS -DHASPROCFS_PFSROOT -DHAS
BUFQ_H -DHAS9660FS=1 -DHASMSDOSFS=1 -DHASKERNFS -DHASKERNFS_KFS_KT -DHASI_FFS1 -
DHASEFFNLINK=i_ffs_effnlink -DHASEXT2FS -DHASI_E2FS_PTR -DHASLFS -DHASPTYFS -DHA
SNFSVATTRP -DHAS_ADVLOCK_ARGS -DHAS_LWP_H -DHASCWDINFO -DHAS_SYS_PIPEH -DHASSTAT
VFS -DUVM -I/usr/pkgsrc/sysutils/lsof/work/lsof_4.76/lsof_4.76_src/dialects/n+ob
sd/include -DHAS_UVM_INCL -DLSOF_VSTR=\"3.99.20\"  -O -DLSOF_MORE_SECURE=0 -DLSO
F_LESS_SECURE_SOCKETS=0 -c dnode.c
dnode.c: In function `process_node':
dnode.c:186: error: storage size of `lf' isn't known
*** Error code 1

The problem is that 'struct lockf' isn't defined --- in fact, I can't find
it defined anywhere.  On 3.0, it's in sys/lockf.h; the file exists on my
-current machines, but it doesn't define the structure.

                --Steven M. Bellovin, http://www.cs.columbia.edu/~smb