CONFIG_ARN5307 is not available for thedefaultarchitecture x86.
Result is shown for architecture m68k

Arnewsh 5307 board support

configname: CONFIG_ARN5307

Linux Kernel Configuration
└─>Arnewsh 5307 board support
In linux kernel since version 2.6.12  
Support for the Arnewsh 5307 board.

selects
CONFIG_ARNEWSH

depends
CONFIG_M5307