CONFIG_H8300_IDE_ALT is not available for thedefaultarchitecture x86.
Result is shown for architecture h8300
default or selected kernelversion does not have config value CONFIG_H8300_IDE_ALT.
Result is shown for kernelversion 6.2.5

IDE register alternate address

configname: CONFIG_H8300_IDE_ALT

Linux Kernel Configuration
└─>IDE Extra configuration
└─>IDE register alternate address
In linux kernel since version 2.6.12  
IDE alternate registers address