pgsql: Split macros from visibilitymap.h into a separate header

Split macros from visibilitymap.h into a separate header

That allows to include just visibilitymapdefs.h from file.c, and in turn,
remove include of postgres.h from relcache.h.

Reported-by: Andres Freund
Discussion: https://postgr.es/m/20210913232614.czafiubr435l6egi%40alap3.anarazel.de
Author: Alexander Korotkov
Reviewed-by: Andres Freund, Tom Lane, Alvaro Herrera
Backpatch-through: 13

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b92f9f74436c48054e7743548edc8ca50e97c6b1

Modified Files
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src/bin/pg_upgrade/file.c              |  2 +-
src/include/access/visibilitymap.h     | 10 +---------
src/include/access/visibilitymapdefs.h | 25 +++++++++++++++++++++++++
src/include/utils/relcache.h           |  1 -
4 files changed, 27 insertions(+), 11 deletions(-)