How to link a static lib to grpc Makefile?

[xia rui]

Hello, everyone.

I am trying to use a third party lib in grpc. I have installed the static lib to linux OS with `make install`. Now I need to add `-llog4cpp -pthread` to the make command of grpc.

I have tried to add `-llog4cpp -pthread` to `LDFLAGS` in `build.yaml` and regenerate `Makefile`. But, the grpc code actually does not link to the static lib.

So where is the correct position to add `-llog4cpp -pthread` in the grpc source code

Thank you for your time.

Best wishes,

Xia Rui