pgsql: Fix vpath build break, induced by Bruce's recent commit.

Log Message:
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Fix vpath build break, induced by Bruce's recent commit.

Modified Files:
--------------
pgsql/src:
Makefile.shlib (r1.80 -> r1.81)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/Makefile.shlib.diff?r1=1.80&r2=1.81)
pgsql/src/interfaces/ecpg/ecpglib:
Makefile (r1.27 -> r1.28)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/interfaces/ecpg/ecpglib/Makefile.diff?r1=1.27&r2=1.28)
pgsql/src/interfaces/libpq:
Makefile (r1.116 -> r1.117)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/interfaces/libpq/Makefile.diff?r1=1.116&r2=1.117)