CONFIG_ALPHA_JENSEN is not available for thedefaultarchitecture x86.
Result is shown for architecture alpha

Jensen

modulename: sys_jensen.ko

configname: CONFIG_ALPHA_JENSEN

Alpha system type
└─>Jensen
In linux kernel since version 2.6.12  
DEC PC 150 AXP (aka Jensen): This is a very old Digital system - one
of the first-generation Alpha systems. A number of these systems
seem to be available on the second- hand market. The Jensen is a
floor-standing tower system which originally used a 150MHz 21064 It
used programmable logic to interface a 486 EISA I/O bridge to the
CPU.

source code: