Fix kernel builds with "options NFS_DEBUG" that
were broken by r276096. Also delete the two
kernel options NFS_GATHERDELAY, NFS_WDELAYHASHSIZ
which are no longer used.

Reported by:	bz


git-svn-id: svn+ssh://svn.freebsd.org/base/head@276140 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f