- Copy stable/10 (r259064) to releng/10.0 as part of the
10.0-RELEASE cycle.
- Update __FreeBSD_version [1]
- Set branch name to -RC1

[1] 10.0-CURRENT __FreeBSD_version value ended at '55', so
start releng/10.0 at '100' so the branch is started with
a value ending in zero.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC r256425:

Centralize the detection logic for the Hyper-V hypervisor.

Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
Reviewed by: gibbs, grehan
Approved by: re (gjb)

sys/sys/systm.h:
* Add a new VM_GUEST type, VM_GUEST_HV (HyperV guest).

sys/dev/hyperv/vmbus/hv_vmbus_drv_freebsd.c:
sys/dev/hyperv/vmbus/hv_hv.c:
sys/dev/hyperv/stordisengage/hv_ata_pci_disengage.c:
* Set vm_guest to VM_GUEST_HV and use that on other HyperV related
devices instead of cloning the cpuid hypervisor check.
* Cleanup the vmbus_identify function.
------------------------------------------------------------------------

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

In sys/dev/hyperv, fix a number of gcc warnings about usage of anonymous
union members in strict C99, by giving them names. While here, add some
FreeBSD keywords where they were missing.

Approved by: re (gjb)
Reviewed by: grehan

Correct panic caused by attaching both Xen PV and HyperV virtualization
aware drivers on Xen hypervisors that advertise support for some
HyperV features.

x86/xen/hvm.c:
When running in HVM mode on a Xen hypervisor, set vm_guest
to VM_GUEST_XEN so other virtualization aware components in
the FreeBSD kernel can detect this mode is active.

dev/hyperv/vmbus/hv_hv.c:
Use vm_guest to ignore Xen's HyperV emulation when Xen is
detected and Xen PV drivers are active.

Reported by: Shanker Balan
Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
Reviewed by: gibbs
Approved by: re (Xen blanket)

Import Hyper-V paravirtualized drivers from projects/hyperv
branch into head.

Approved by: re@ (hrs)
Obtained from: Microsoft, NetApp, and Citrix.

Latest update from Microsoft.

Obtained from: Microsoft Hyper-v dev team

Microsoft have changed their policy on how the hyper-v code will
be pulled into FreeBSD. From now, FreeBSD will be considered the
upstream repo.

First step: move the drivers away from the contrib area and into
the base system.

A follow-on commit will include the drivers in the amd64 GENERIC kernel.

Import driver source from hyperv-20130502 vendor branch.

Tag hyperv 20130502

Initial import of the Microsoft HyperV 'enlightened' drivers.

From https://github.com/FreeBSDonHyper-V/VendorBranchForFreeBSDonHyper-V
rev: 99eaa0ddb0485c9d76046664100f6beb1a0a0c58