CONFIG_XEN_PV is not available for thedefaultarchitecture x86.
Result is shown for architecture 64BIT

Xen PV guest support

modulename: setup.ko

and/or

apic.ko

and/or

pmu.ko

and/or

suspend_pv.ko

and/or

p2m.ko

and/or

enlighten_pv.ko

and/or

mmu_pv.ko

and/or

irq.ko

and/or

multicalls.ko

and/or

xen-asm.ko

configname: CONFIG_XEN_PV

Linux Kernel Configuration
└─>Processor type and features
└─>Linux guest support
└─>Xen PV guest support
In linux kernel since version 3.10 (release Date: 2013-06-30)  
Support running as a Xen PV guest.