CONFIG_M68KCLASSIC is not available for thedefaultarchitecture x86.
Result is shown for architecture m68k

Classic M68K CPU family support

configname: CONFIG_M68KCLASSIC

CPU family support
└─>Classic M68K CPU family support
In linux kernel since version 3.1 (release Date: 2011-10-24)  
is selected by
CONFIG_SUN3
CONFIG_M68060