Fix build-error (pointy hat; didn't merge full up-to-date code)

MFC after:	21 days
X-MFC-to:	stable/10 stable/9
X-MFC-with:	274116


git-svn-id: svn+ssh://svn.freebsd.org/base/head@274120 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f
Make libdpv [dpv(3)] WARNS=6 clean for clang on -CURRENT.
NB: aka unbreak the build

Reviewed by:	shurd
MFC after:	21 days
X-MFC-to:	stable/10 stable/9
X-MFC-with:	274116 274120


git-svn-id: svn+ssh://svn.freebsd.org/base/head@274121 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f