Let dependent libraries and found leak out from package config

Needed in Lunchbox to do selective library linking of SKV with optional
dependent libraries:
```
if(SKV_FOUND)
  list(APPEND LUNCHBOX_LINK_LIBRARIES ${SKV_CLIENT_LIBRARY}
    ${SKV_COMMON_LIBRARY} ${IT_API_LIBRARY} ${FXLOGGER_LIBRARY})
  if(SKV_OFED_FOUND)
    list(APPEND LUNCHBOX_LINK_LIBRARIES ${SKV_OFED_LIBRARIES})
  endif()
endif()
```