pgsql: Fixed memory leak bugs found by Martijn Oosterhout.

Log Message:
-----------
Fixed memory leak bugs found by Martijn Oosterhout.

Tags:
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REL8_0_STABLE

Modified Files:
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    pgsql/src/interfaces/ecpg/compatlib:
        informix.c (r1.38 -> r1.38.4.1)

(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/interfaces/ecpg/compatlib/informix.c.diff?r1=1.38&r2=1.38.4.1)
    pgsql/src/interfaces/ecpg/ecpglib:
        execute.c (r1.38.4.3 -> r1.38.4.4)

(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/interfaces/ecpg/ecpglib/execute.c.diff?r1=1.38.4.3&r2=1.38.4.4)
    pgsql/src/interfaces/ecpg/pgtypeslib:
        numeric.c (r1.20 -> r1.20.4.1)

(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/interfaces/ecpg/pgtypeslib/numeric.c.diff?r1=1.20&r2=1.20.4.1)