MFC: r322076

MFC:	r322076

Detect hypervisor early so that we set lower hz on it.
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_M   .
M    sys/amd64/amd64/machdep.c
M    sys/amd64/include/md_var.h
M    sys/i386/i386/machdep.c
M    sys/i386/include/md_var.h
M    sys/x86/x86/identcpu.c

git-svn-id: svn://svn.freebsd.org/base/stable/10@322205 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f