Merge projects/bhyve_svm into HEAD.

After this change bhyve supports AMD processors with the SVM/AMD-V hardware
extensions.

More details available here:
https://lists.freebsd.org/pipermail/freebsd-virtualization/2014-October/002905.html

Submitted by:	Anish Gupta (akgupt3@gmail.com)
Tested by:	Benjamin Perrault (ben.perrault@gmail.com)
Tested by:	Willem Jan Withagen (wjw@digiware.nl)


git-svn-id: svn+ssh://svn.freebsd.org/base/head@273375 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f