[TRUSTY ARM/ARM64] [PULL] UBUNTU: support reboot and poweroff for VM

[Ming Lei]

Hi,

The current trusty kernel can't support 'reboot' and 'poweroff' for
arm64 and arm VM because of missing KVM PSCI v0.2 feature.

So I backported the KVM PSCI v0.2 patchset from upstream(v3.16).

       BugLink: http://bugs.launchpad.net/bugs/1455372

The patch of 'of: reimplement the matching method for
__of_match_node()' is needed, because it fixes probe
issue for 'arm,psci-0.2'.

The following 3 patches are backported for avoiding
patch conflicts, which all are PSCI related. Then all
other patches are for PSCI v0.2 support, and belong to
one same patchset when landing to upstream.

SRU Justification:
    Impact: 'reboot' &'poweroff' will hang inside VM kernel
    Fix: backport PSCI v0.2 patches
    Testcase: boot one arm64 trusty VM, and run 'reboot'/'poweroff'

So please pull the top 20 patches from below tree/branch:

     git://kernel.ubuntu.com/git/ming/ubuntu-trusty.git  kvm-psci-backport

05e2de2 arm64: KVM: Enable minimalistic support for Cortex-A53
aa40fa6 ARM: Check if a CPU has gone offline
a831891 Documentation: devicetree: Add new binding for PSCIv0.2
fe60ff1 PSCI: Add initial support for PSCIv0.2 functions
10795f4 ARM/ARM64: KVM: Advertise KVM_CAP_ARM_PSCI_0_2 to user space
5f2e3f7 ARM/ARM64: KVM: Emulate PSCI v0.2 CPU_SUSPEND
9271d53 ARM/ARM64: KVM: Fix CPU_ON emulation for PSCI v0.2
fb4e124 ARM/ARM64: KVM: Emulate PSCI v0.2 MIGRATE_INFO_TYPE and related function
34c6d4d ARM/ARM64: KVM: Emulate PSCI v0.2 AFFINITY_INFO
3ff7ae5 ARM/ARM64: KVM: Emulate PSCI v0.2 SYSTEM_OFF and SYSTEM_RESET
ab06cba KVM: Add KVM_EXIT_SYSTEM_EVENT to user space API header
107daef ARM/ARM64: KVM: Make kvm_psci_call() return convention more flexible
b65b982 KVM: Documentation: Add info regarding KVM_ARM_VCPU_PSCI_0_2 feature
bdf32ab ARM/ARM64: KVM: Add base for PSCI v0.2 emulation
9cc0b95 ARM/ARM64: KVM: Add common header for PSCI related defines
b65857e KVM: Add capability to advertise PSCI v0.2 support
9fe5eca arm: KVM: Don't return PSCI_INVAL if waitqueue is inactive
e1e3f55 arm64: remove return value form psci_init()
75d7cdb arm64: remove redundant "psci:" prefixes
774b5b2 of: reimplement the matching method for __of_match_node()


Thanks,
Ming