[COMMITTERS] pgsql: Remove obsolete comments about functional dependencies

Remove obsolete comments about functional dependencies

Initial submitted versions of the functional dependencies patch ignored
row groups that were smaller than a configured size.  However, that
consideration was removed in late stages of the patch just before
commit, but some comments referring to it remained.  Remove them to
avoid confusion.

Author: Atsushi Torikoshi
Discussion: https://postgr.es/m/7cfb23fc-4493-9c02-5da9-e505fd0115d2@lab.ntt.co.jp

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/c28e4f4dc6aeb75cf35f1339cbe3387263e0e69b

Modified Files
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src/backend/statistics/README.dependencies | 4 ----
src/backend/statistics/dependencies.c      | 8 --------
2 files changed, 12 deletions(-)