CONFIG_P1023_RDB is not available for thedefaultarchitecture x86.
Result is shown for architecture powerpc

Freescale P1023 RDB

modulename: p1023_rdb.ko

configname: CONFIG_P1023_RDB

Linux Kernel Configuration
└─>Freescale Book-E Machine Type
└─>Freescale P1023 RDB
In linux kernel since version 3.10 (release Date: 2013-06-30)  
This option enables support for the P1023 RDB board.

source code: