bhyve: add table dump functions for basl

bhyve: add table dump functions for basl

Developing an ACPI table compiler isn't quite easy. It's helpful if you
can take a look at the ACPI tables created by the compiler.

The dump functions can either dump a ACPI table which was copied into
guest memory or a ACPI table provided for qemu's ACPI table loader.

Reviewed by:		jhb, markj
Approved by:		manu (mentor)
MFC after:		2 weeks
Sponsored by:		Beckhoff Automation GmbH & Co. KG
Differential Revision:	https://reviews.freebsd.org/D36985