CONFIG_MACH_RX3715 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm
default or selected kernelversion does not have config value CONFIG_MACH_RX3715.
Result is shown for kernelversion 6.9.9

HP iPAQ rx3715

modulename: mach-rx3715.ko

configname: CONFIG_MACH_RX3715

Linux Kernel Configuration
└─>Samsung S3C24XX SoCs (deprecated, see help)
└─>Samsung S3C24XX SoCs Support
└─>HP iPAQ rx3715
In linux kernel since version 2.6.12  
Say Y here if you are using the HP iPAQ rx3715.