Обсуждение: pgsql: Fix outdated comments regarding TupleTableSlots

Fix outdated comments regarding TupleTableSlots

The tts_flag is named TTS_FLAG_SHOULDFREE, so use that instead of
TTS_SHOULDFREE, which is the name of the macro that checks for that flag.

Additionally, 4da597edf got rid of the TupleTableSlot.tts_tuple field but
forgot to update a comment which referenced that field.  Fix that.

Reported-by: Zhen Mingyang <zhenmingyang@yeah.net>
Reported-by: Richard Guo <guofenglinux@gmail.com>
Discussion: https://postgr.es/m/1a96696c.9d3.187193989c3.Coremail.zhenmingyang@yeah.net

Branch
------
master

Details
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https://git.postgresql.org/pg/commitdiff/902ecd3bd4e733d273e69fd420df6fab4ffbe79b

Modified Files
--------------
src/backend/executor/execTuples.c |  9 +++++----
src/include/executor/tuptable.h   | 10 +++++-----
2 files changed, 10 insertions(+), 9 deletions(-)