pgsql: Code review for avoidance of direct cross-module links.

Code review for avoidance of direct cross-module links.

Remove $(pkglibdir) from $(rpathdir), since commits
d51924be886c2a05e691fa05b16cb6b30ab8370f and
eda04886c1e048d695728206504ab4198462168e removed direct linkage to
objects stored there. Users are unlikely to notice the difference.
Accompany every $(python_libspec) with $(python_additional_libs); this
doesn't fix a demonstrated bug, but it might do so on rare Python
configurations. With these changes, AIX ceases to be a special case.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/acd73ad1a17f7aed6a914dd9c331f1043d89988d

Modified Files
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contrib/hstore_plperl/Makefile | 5 -----
contrib/hstore_plpython/Makefile | 7 +------
contrib/ltree_plpython/Makefile | 7 +------
3 files changed, 2 insertions(+), 17 deletions(-)