kvm: Check for HTL extension granted

We need it thought it seems it doesn't work in
all our testcases.

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>

kvm.c

@@ -64,6 +64,7 @@ struct {
 	{ DEFINE_KVM_EXT(KVM_CAP_USER_MEMORY) },
 	{ DEFINE_KVM_EXT(KVM_CAP_IRQ_ROUTING) },
 	{ DEFINE_KVM_EXT(KVM_CAP_IRQCHIP) },
+	{ DEFINE_KVM_EXT(KVM_CAP_HLT) },
 	{ DEFINE_KVM_EXT(KVM_CAP_IRQ_INJECT_STATUS) },
 };