x86/xen: Move pv irq related functions under CONFIG_XEN_PV umbrella

All functions in arch/x86/xen/irq.c and arch/x86/xen/xen-asm*.S are
specific to PV guests. Include them in the kernel with CONFIG_XEN_PV only.

Make the PV specific code in arch/x86/entry/entry_*.S dependent on
CONFIG_XEN_PV instead of CONFIG_XEN.

The HVM specific code should depend on CONFIG_XEN_PVHVM.

While at it reformat the Makefile to make it more readable.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: xen-devel@lists.xenproject.org
Cc: virtualization@lists.linux-foundation.org
Cc: akataria@vmware.com
Cc: rusty@rustcorp.com.au
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/20180828074026.820-2-jgross@suse.com

arch/x86/xen/Makefile

@@ -12,25 +12,46 @@ endif
 # Make sure early boot has no stackprotector
 nostackp := $(call cc-option, -fno-stack-protector)
 CFLAGS_enlighten_pv.o		:= $(nostackp)
-CFLAGS_mmu_pv.o		:= $(nostackp)
+CFLAGS_mmu_pv.o			:= $(nostackp)
 
-obj-y		:= enlighten.o multicalls.o mmu.o irq.o \
-			time.o xen-asm.o xen-asm_$(BITS).o \
-			grant-table.o suspend.o platform-pci-unplug.o
+obj-y				+= enlighten.o
+obj-y				+= multicalls.o
+obj-y				+= mmu.o
+obj-y				+= time.o
+obj-y				+= grant-table.o
+obj-y				+= suspend.o
+obj-y				+= platform-pci-unplug.o
 
-obj-$(CONFIG_XEN_PVHVM)		+= enlighten_hvm.o mmu_hvm.o suspend_hvm.o
-obj-$(CONFIG_XEN_PV)			+= setup.o apic.o pmu.o suspend_pv.o \
-						p2m.o enlighten_pv.o mmu_pv.o
-obj-$(CONFIG_XEN_PVH)			+= enlighten_pvh.o
+obj-$(CONFIG_XEN_PVHVM)		+= enlighten_hvm.o
+obj-$(CONFIG_XEN_PVHVM)		+= mmu_hvm.o
+obj-$(CONFIG_XEN_PVHVM)		+= suspend_hvm.o
 
-obj-$(CONFIG_EVENT_TRACING) += trace.o
+obj-$(CONFIG_XEN_PV)		+= setup.o
+obj-$(CONFIG_XEN_PV)		+= apic.o
+obj-$(CONFIG_XEN_PV)		+= pmu.o
+obj-$(CONFIG_XEN_PV)		+= suspend_pv.o
+obj-$(CONFIG_XEN_PV)		+= p2m.o
+obj-$(CONFIG_XEN_PV)		+= enlighten_pv.o
+obj-$(CONFIG_XEN_PV)		+= mmu_pv.o
+obj-$(CONFIG_XEN_PV)		+= irq.o
+obj-$(CONFIG_XEN_PV)		+= xen-asm.o
+obj-$(CONFIG_XEN_PV)		+= xen-asm_$(BITS).o
+
+obj-$(CONFIG_XEN_PVH)		+= enlighten_pvh.o
+obj-$(CONFIG_XEN_PVH)	 	+= xen-pvh.o
+
+obj-$(CONFIG_EVENT_TRACING)	+= trace.o
 
 obj-$(CONFIG_SMP)		+= smp.o
 obj-$(CONFIG_XEN_PV_SMP)  	+= smp_pv.o
 obj-$(CONFIG_XEN_PVHVM_SMP)  	+= smp_hvm.o
+
 obj-$(CONFIG_PARAVIRT_SPINLOCKS)+= spinlock.o
+
 obj-$(CONFIG_XEN_DEBUG_FS)	+= debugfs.o
+
 obj-$(CONFIG_XEN_DOM0)		+= vga.o
+
 obj-$(CONFIG_SWIOTLB_XEN)	+= pci-swiotlb-xen.o
+
 obj-$(CONFIG_XEN_EFI)		+= efi.o
-obj-$(CONFIG_XEN_PVH)	 	+= xen-pvh.o