Style fixes.


git-svn-id: svn+ssh://svn.freebsd.org/base/head@272297 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f
Be prepared that set_dumper() might fail even when resetting it or prefix
the call with (void) to document that we intentionally ignore the return
value - no way to handle an error in case of device disappearing.


git-svn-id: svn+ssh://svn.freebsd.org/base/head@272298 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f