KVM: arm64: Change CONFIG_KVM to a menuconfig entry

Changing CONFIG_KVM to be a 'menuconfig' entry in Kconfig mean that we
can straightforwardly enumerate optional features, such as the virtual
PMU device as dependent options.
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200505154520.194120-4-tabba@google.com

arch/arm64/kvm/Kconfig

@@ -3,7 +3,6 @@
 # KVM configuration
 #
 
-source "virt/kvm/Kconfig"
 source "virt/lib/Kconfig"
 
 menuconfig VIRTUALIZATION
@@ -18,7 +17,7 @@ menuconfig VIRTUALIZATION
 
 if VIRTUALIZATION
 
-config KVM
+menuconfig KVM
 	bool "Kernel-based Virtual Machine (KVM) support"
 	depends on OF
 	# for TASKSTATS/TASK_DELAY_ACCT:
@@ -33,7 +32,6 @@ config KVM
 	select KVM_VFIO
 	select HAVE_KVM_EVENTFD
 	select HAVE_KVM_IRQFD
-	select KVM_ARM_PMU if HW_PERF_EVENTS
 	select HAVE_KVM_MSI
 	select HAVE_KVM_IRQCHIP
 	select HAVE_KVM_IRQ_ROUTING
@@ -47,13 +45,21 @@ config KVM
 
 	  If unsure, say N.
 
+if KVM
+
+source "virt/kvm/Kconfig"
+
 config KVM_ARM_PMU
-	bool
+	bool "Virtual Performance Monitoring Unit (PMU) support"
+	depends on HW_PERF_EVENTS
+	default y
 	---help---
 	  Adds support for a virtual Performance Monitoring Unit (PMU) in
 	  virtual machines.
 
 config KVM_INDIRECT_VECTORS
-       def_bool KVM && (HARDEN_BRANCH_PREDICTOR || HARDEN_EL2_VECTORS)
+	def_bool HARDEN_BRANCH_PREDICTOR || HARDEN_EL2_VECTORS
+
+endif # KVM
 
 endif # VIRTUALIZATION