out of src tree builds are broken
Currently, out of tree builds of pslib are broken because psErrorText.h is
bundled with a pslib dist and not generated at build time. The failure results
from ${topdir_dir}/src not being included. (${top_srcdir} and ${top_builddir}
are the same for in-tree builds). I tried making it a nodist_* header so it
would be rebuilt and placed into the build tree but psParseErrorCodes can't
currently handle psErrorText.h.in and psErrorText.h being in different
directories (hardwired assumption). psParseErrorCodes should probably be fixed
some day but for the moment it seems sufficent to push -I${top_srcdir}/src into
SRCINC.
patch to fix out of src tree builds