pgsql: Add macro for maximum statistics target

Add macro for maximum statistics target

The number of places where 10000 was hardcoded had grown a bit beyond
the comfort level. Introduce a macro MAX_STATISTICS_TARGET instead.

Reviewed-by: Tomas Vondra <tomas(dot)vondra(at)enterprisedb(dot)com>
Discussion: https://www.postgresql.org/message-id/flat/d6069765-5971-04d3-c10d-e4f7b2e9c459%40eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/7a7f60aef8bf86b1a94908e20edd107fa9da4f3d

Modified Files
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src/backend/commands/statscmds.c | 4 ++--
src/backend/commands/tablecmds.c | 5 +++--
src/backend/statistics/extended_stats.c | 2 +-
src/backend/utils/misc/guc_tables.c | 2 +-
src/include/catalog/pg_attribute.h | 2 +-
src/include/commands/vacuum.h | 7 +++++++
src/include/statistics/statistics.h | 4 ++--
7 files changed, 17 insertions(+), 9 deletions(-)