Make it possible to opt-out from Hyper-V support, for minimized kernels
that never will by run under Hyper-V. (eg. high-density virtualization
or embedded systems)

Average distro kernel will leave it on, therefore default to y.

Signed-off-by: Enrico Weigelt <info@metux.net>
---
 arch/x86/Kconfig                 | 11 +++++++++++
 arch/x86/kernel/cpu/Makefile     |  4 ++--
 arch/x86/kernel/cpu/hypervisor.c |  2 ++
 drivers/hv/Kconfig               |  2 +-
 4 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index eff12460cb3c..57d20591d6ee 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig

@@ -812,6 +812,17 @@ config VMWARE_GUEST
 	  density virtualization or embedded systems running (para)virtualized
 	  workloads.
 
+config HYPERV_GUEST
+	bool "Hyper-V Guest support"
+	default y
+	help
+	  This option enables several optimizations for running under the
+	  Hyper-V hypervisor.
+
+	  Disabling it saves a few kb, for stripped down kernels eg. in high