pgsql: Add parse_analyze_withcb()

Add parse_analyze_withcb()

This extracts code from pg_analyze_and_rewrite_withcb() into a
separate function that mirrors the existing
parse_analyze_fixedparams() and parse_analyze_varparams().

Reviewed-by: Nathan Bossart <bossartn@amazon.com>
Discussion: https://www.postgresql.org/message-id/flat/c67ce276-52b4-0239-dc0e-39875bf81840@enterprisedb.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/df4c3cbd8f4f619785c735669150e3a1df9cf7ca

Modified Files
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src/backend/parser/analyze.c | 38 ++++++++++++++++++++++++++++++++++++++
src/backend/tcop/postgres.c  | 22 ++--------------------
src/include/parser/analyze.h |  5 +++++
3 files changed, 45 insertions(+), 20 deletions(-)