Fix build errors with bitbake

8b976659 has build fails with a pldm bitbake recipe. The fix was mostly
about using top_srcdir instead of top_builddir.

Change-Id: Ic3ef0e01997921174d28ae10e66e7bdd17c52af8
Signed-off-by: Deepak Kodihalli <dkodihal@in.ibm.com>