KVM: cleanup arch/x86/kvm/Makefile

Use proper foo-y style list additions to cleanup all the conditionals,
move module selection after compound object selection and remove the
superflous comment.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Avi Kivity <avi@redhat.com>

arch/x86/kvm/Makefile

-#
-# Makefile for Kernel-based Virtual Machine module
-#
-
-common-objs = $(addprefix ../../../virt/kvm/, kvm_main.o ioapic.o \
-                coalesced_mmio.o irq_comm.o)
-ifeq ($(CONFIG_KVM_TRACE),y)
-common-objs += $(addprefix ../../../virt/kvm/, kvm_trace.o)
-endif
-ifeq ($(CONFIG_IOMMU_API),y)
-common-objs += $(addprefix ../../../virt/kvm/, iommu.o)
-endif
 
 EXTRA_CFLAGS += -Ivirt/kvm -Iarch/x86/kvm
 
-kvm-objs := $(common-objs) x86.o mmu.o x86_emulate.o i8259.o irq.o lapic.o \
-	i8254.o timer.o
-obj-$(CONFIG_KVM) += kvm.o
-kvm-intel-objs = vmx.o
-obj-$(CONFIG_KVM_INTEL) += kvm-intel.o
-kvm-amd-objs = svm.o
-obj-$(CONFIG_KVM_AMD) += kvm-amd.o
+kvm-y			+= $(addprefix ../../../virt/kvm/, kvm_main.o ioapic.o \
+				coalesced_mmio.o irq_comm.o)
+kvm-$(CONFIG_KVM_TRACE)	+= $(addprefix ../../../virt/kvm/, kvm_trace.o)
+kvm-$(CONFIG_IOMMU_API)	+= $(addprefix ../../../virt/kvm/, iommu.o)
+
+kvm-y			+= x86.o mmu.o x86_emulate.o i8259.o irq.o lapic.o \
+			   i8254.o timer.o
+kvm-intel-y		+= vmx.o
+kvm-amd-y		+= svm.o
+
+obj-$(CONFIG_KVM)	+= kvm.o
+obj-$(CONFIG_KVM_INTEL)	+= kvm-intel.o
+obj-$(CONFIG_KVM_AMD)	+= kvm-amd.o