pgsql: Run pgindent on heapam.c

Run pgindent on heapam.c

An upcoming patch by Melanie Plageman does some refactoring work in this
area.  Run pgindent on that file now before making any changes so that
it's easier to maintain/evolve each of the individual patches doing the
refactor work.  Additionally, add a few new required typedefs to the list
to make it easier to do future pgindent runs on this file during the
refactor work.

Discussion: https://postgr.es/m/CAAKRu_YSOnhKsDyFcqJsKtBSrd32DP-jjXmv7hL0BPD-z0TGXQ@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/009dbdea02d74c72db2d1a57d5299f94f91fa975

Modified Files
--------------
src/backend/access/heap/heapam.c | 17 +++++++++--------
src/tools/pgindent/typedefs.list |  3 +++
2 files changed, 12 insertions(+), 8 deletions(-)