pgsql: Add 'missing_ok' argument to build_attrmap_by_name

Add 'missing_ok' argument to build_attrmap_by_name

When it's given as true, return a 0 in the position of the missing
column rather than raising an error.

This is currently unused, but it allows us to reimplement column
permission checking in a subsequent commit. It seems worth breaking
into a separate commit because it affects unrelated code.

Author: Amit Langote <amitlangote09(at)gmail(dot)com>
Discussion: https://postgr.es/m/CA+HiwqFfiai=qBxPDTjaio_ZcaqUKh+FC=prESrB8ogZgFNNNQ@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/ad86d159b6ab90b195b06fb5c7b593900a7f9cd8

Modified Files
--------------
src/backend/access/common/attmap.c | 14 ++++++++++----
src/backend/access/common/tupconvert.c | 2 +-
src/backend/catalog/partition.c | 3 ++-
src/backend/commands/indexcmds.c | 3 ++-
src/backend/commands/tablecmds.c | 24 ++++++++++++++++--------
src/backend/executor/execMain.c | 11 +++++++----
src/backend/executor/execPartition.c | 15 ++++++++++-----
src/backend/parser/parse_utilcmd.c | 3 ++-
src/backend/replication/pgoutput/pgoutput.c | 2 +-
src/include/access/attmap.h | 6 ++++--
10 files changed, 55 insertions(+), 28 deletions(-)