pgsql: Fix a couple of places that would loop forever if attempts to

Log Message:
-----------
Fix a couple of places that would loop forever if attempts to read a stdio file
set ferror() but never set feof(). This is known to be the case for recent
glibc when trying to read a directory as a file, and might be true for other
platforms/cases too. Per report from Ed L. (There is more that we ought to
do about his report, but this is one easily identifiable issue.)

Tags:
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REL8_0_STABLE

Modified Files:
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pgsql/src/backend/commands:
copy.c (r1.236.4.3 -> r1.236.4.4)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/copy.c?r1=1.236.4.3&r2=1.236.4.4)
pgsql/src/backend/libpq:
hba.c (r1.136.4.1 -> r1.136.4.2)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/libpq/hba.c?r1=1.136.4.1&r2=1.136.4.2)
pgsql/src/interfaces/libpq:
fe-connect.c (r1.301.4.6 -> r1.301.4.7)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/interfaces/libpq/fe-connect.c?r1=1.301.4.6&r2=1.301.4.7)