pgsql: Removal unused function parameter in CopyReadBinaryAttribute.

Removal unused function parameter in CopyReadBinaryAttribute.

The function parameter column_no is not used in CopyReadBinaryAttribute,
this can be removed.

Commit 0e319c7ad7 removed the usage of column_no parameter in function
CopyReadBinaryAttribute but forgot to remove the parameter.

Reported-by: Vignesh C
Author: Vignesh C
Discussion: https://postgr.es/m/CALDaNm1TYSNTfqx_jfz9_mwEZ2Er=dZnu++duXpC1uQo1cG=WA@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/74b4d78e037c1d4d55fd61f1b58c161e6249dfde

Modified Files
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src/backend/commands/copy.c | 9 ++-------
1 file changed, 2 insertions(+), 7 deletions(-)