Allow out-of-source builds.

- Clean up lib/cpp/Makefile.am to use AM_CXXFLAGS etc instead of
  target-specific so we can take advantage of default flags.
- Use top_builddir in a few places instead of top_srcdir.


git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@666489 13f79535-47bb-0310-9956-ffa450edef68
2 files changed