pgsql: Limit max parameter number with MaxAllocSize

Limit max parameter number with MaxAllocSize

MaxAllocSize puts an upper bound on the largest possible parameter
number ($268435455).  Use that limit instead of INT_MAX to report that
no parameters exist beyond that point instead of reporting an error
about the maximum allocation size being exceeded.

Author: Erik Wienhold <ewie@ewie.name>
Discussion: https://www.postgresql.org/message-id/flat/5d216d1c-91f6-4cbe-95e2-b4cbd930520c@ewie.name

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/9c2e660b07fc16bdd79c25047cce6cde2acb3f37

Modified Files
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src/backend/parser/parse_param.c      | 3 ++-
src/test/regress/expected/prepare.out | 5 +++++
src/test/regress/sql/prepare.sql      | 3 +++
3 files changed, 10 insertions(+), 1 deletion(-)