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


configname: CONFIG_ARCH_PRPMC1100

Linux Kernel Configuration
└─>Intel IXP4xx Implementation Options
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>.