CONFIG_ARCH_PXA_V7 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

ARMv7 (PXA95x) based systems

configname: CONFIG_ARCH_PXA_V7

Linux Kernel Configuration
└─>Intel PXA2xx/PXA3xx Implementations
└─>ARMv7 (PXA95x) based systems
In linux kernel since version 3.3 (release Date: 2012-03-18)  
depends
CONFIG_ARCH_PXA