CONFIG_MACH_RX1950 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm
HP iPAQ rx1950
configname: CONFIG_MACH_RX1950
Linux Kernel Configuration
└─>Samsung S3C24XX SoCs Support
└─>HP iPAQ rx1950
In linux kernel since version 2.6.35 (release Date: 2010-08-01)
Say Y here if you're using HP iPAQ rx1950