CONFIG_ARCH_PRPMC1100 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm
default or selected kernelversion does not have config value CONFIG_ARCH_PRPMC1100.
Result is shown for kernelversion 6.9.5

PrPMC1100

configname: CONFIG_ARCH_PRPMC1100

Linux Kernel Configuration
└─>Intel IXP4xx Implementation Options
└─>PrPMC1100
In linux kernel since version 2.6.12  
Say 'Y' here if you want your kernel to support the Motorola
PrPCM1100 Processor Mezanine Module. For more information on
this platform, see <file:Documentation/arm/IXP4xx>.