Fix the add_fbthrift_cpp_library CMake function

Summary: `${service}_processmap_serialization.cpp` was mistakenly added to source files in D80006546 while we do not generate this file. Fix it to unbreak fboss and other users of `add_fbthrift_cpp_library`.

Reviewed By: tanquer

Differential Revision: D80189355

fbshipit-source-id: e24f3d38ca8f1762c2636c6c4e4bc5e80aa0699d

Author: vitaut

build/fbcode_builder/CMake/FBThriftCppLibrary.cmake

@@ -86,7 +86,6 @@ function(add_fbthrift_cpp_library LIB_NAME THRIFT_FILE)
       "${output_dir}/gen-cpp2/${service}AsyncClient.cpp"
       "${output_dir}/gen-cpp2/${service}_processmap_binary.cpp"
       "${output_dir}/gen-cpp2/${service}_processmap_compact.cpp"
-      "${output_dir}/gen-cpp2/${service}_processmap_serialization.cpp"
     )
   endforeach()