pgsql: Move heaprel struct field next to index rel field.

Move heaprel struct field next to index rel field.

Commit 61b313e4 added a heaprel struct member to IndexVacuumInfo, but
placed it last.  Move the heaprel struct member next to the index struct
member to improve the code's readability.

Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-WznG=TV6S9d3VA=y0vBHbXwnLs9_LLdiML=aNJuHeriwxg@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/a349b86603e11bad811bec111ec5330b9908e525

Modified Files
--------------
src/backend/access/heap/vacuumlazy.c  | 4 ++--
src/backend/catalog/index.c           | 2 +-
src/backend/commands/analyze.c        | 2 +-
src/backend/commands/vacuumparallel.c | 2 +-
src/include/access/genam.h            | 2 +-
5 files changed, 6 insertions(+), 6 deletions(-)