snappy.h conflict

[balshetzer]

Description

when using cmake FetchContent or the cmake release process then the entire directory is used as the include directory. Then, if you also depend on snappy then you get a conflict on snappy.h.

How to reproduce

create a project that uses rdkafka and snappy. Use cmake FetchContent to get rdkafka. Include snappy.h. There is no way to disambiguate.

It would be nice if only the public includes were in an include dir that can be added to the include path.