Fix incorrect reading of 32-bit modinfo by 64-bit loaders.

The various structures in the mod_metadata set of a FreeBSD kernel and
modules contain pointers. The FreeBSD loader correctly deals with a
mismatch in loader and kernel pointer size (e.g. 32-bit i386/ppc
loader, loading 64-bit amd64/ppc64 kernels), but wasn't dealing with
the inverse case where a 64-bit loader was loading a 32-bit kernel.

Reported by:	ktcallbox@gmail.com with a bhyve/i386 and ZFS root install
Differential Revision:	https://reviews.freebsd.org/D1129
Reviewed by:	neel, jhb
MFC after:	1 week


git-svn-id: svn+ssh://svn.freebsd.org/base/head@274407 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f
Fix build.


git-svn-id: svn+ssh://svn.freebsd.org/base/head@274408 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f