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

CONFIG_PPC_MERGE (not configurable)

configname: CONFIG_PPC_MERGE

Linux/PowerPC Kernel Configuration
└─>PPC_MERGE
In linux kernel since version 2.6.15 (release Date: 2006-01-02)  
is selected by
CONFIG_FEC_MPC52xx