Thread: pgsql: Add comments for AlteredTableInfo->rel

Add comments for AlteredTableInfo->rel

The prior commit which introduced it was pretty squalid in terms of
code documentation, so add some comments.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/cc121d5596964f8aac93607e6f14607184558b16

Modified Files
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src/backend/commands/tablecmds.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)