onnxruntime

4cb138aa - Add CMake mlas_private_compile_definitions variable for internal MLAS definitions. (#26225)

Add CMake mlas_private_compile_definitions variable for internal MLAS definitions. (#26225) ### Description <!-- Describe your changes. --> Add CMake `mlas_private_compile_definitions` variable for internal MLAS definitions. ### Motivation and Context <!-- - Why is this change required? What problem does it solve? - If it fixes an open issue, please link to the issue here. --> Refactor so that it is easier to add new private compile definitions for MLAS and related targets.