Remove an unused variable that would be better spelled __func__.

Sponsored by:	DARPA, AFRL


git-svn-id: svn+ssh://svn.freebsd.org/base/head@273612 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f
Fix the build by installing acpi_hpet.h correctly.

Submitted by:	jase
MFC after:	1 week


git-svn-id: svn+ssh://svn.freebsd.org/base/head@273613 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f
Use the __DECONST macro rather than hand rolling the same thing.

Sponsored by:	DARPA, AFRL


git-svn-id: svn+ssh://svn.freebsd.org/base/head@273614 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f