Get rid of code that dealt with the hardware not being able to save/restore
the PAT MSR on guest exit/entry. This workaround was done for a beta release
of VMware Fusion 5 but is no longer needed in later versions.

All Intel CPUs since Nehalem have supported saving and restoring MSR_PAT
in the VM exit and entry controls.

Discussed with:	grehan


git-svn-id: svn+ssh://svn.freebsd.org/base/head@272395 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f