pgsql: Disallow empty passwords in LDAP authentication, the same way we

Log Message:
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Disallow empty passwords in LDAP authentication, the same way
we already do it for PAM.

Tags:
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REL8_3_STABLE

Modified Files:
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pgsql/src/backend/libpq:
auth.c (r1.164.2.1 -> r1.164.2.2)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/libpq/auth.c?r1=1.164.2.1&r2=1.164.2.2)