pgsql: Move check for binary mode and on_error option to the appropriat

Move check for binary mode and on_error option to the appropriate location.

Commit 9e2d870119 placed the check for binary mode and on_error
before default values were inserted, which was not ideal.
This commit moves the check to a more appropriate position
after default values are set.

Additionally, the comment incorrectly mentioned two checks before
inserting defaults, when there are actually three. This commit corrects
that comment.

Author: Atsushi Torikoshi
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/8830518a-28ac-43a2-8a11-1676d9a3cdf8@oss.nttdata.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/a39297ec026c556b1bf2963dde766db31a2c3d2d

Modified Files
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src/backend/commands/copy.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)