pgsql: Further error message fix - Mailing list pgsql-committers

Further error message fix

Further fix of error message changed in commit 74a116a79b4.  The
initial fix was not quite correct.

Discussion: https://www.postgresql.org/message-id/flat/tencent_1EE1430B1E6C18A663B8990F%40qq.com

Branch
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REL_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/a7bdbbadac3b984555d096d9a2765f71906bd9f2

Modified Files
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src/bin/pg_rewind/file_ops.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)