pgsql: Use the GetPGProcByNumber() macro when possible

Use the GetPGProcByNumber() macro when possible

A few places were accessing &ProcGlobal->allProcs directly, so adjust
them to use the accessor macro instead.

Author: Maksim Melnikov <m(dot)melnikov(at)postgrespro(dot)ru>
Reviewed-by: Chao Li <li(dot)evan(dot)chao(at)gmail(dot)com>
Reviewed-by: David Rowley <dgrowleyml(at)gmail(dot)com>
Discussion: https://postgr.es/m/80621c00-aba6-483c-88b1-a845461d1165@postgrespro.ru

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/4c144e0452daa2508a008bb4cde520613bbd386d

Modified Files
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src/backend/access/transam/clog.c | 4 ++--
src/backend/postmaster/pgarch.c | 2 +-
src/backend/postmaster/walsummarizer.c | 2 +-
src/backend/storage/buffer/freelist.c | 2 +-
src/backend/storage/lmgr/lock.c | 6 +++---
src/backend/storage/lmgr/proc.c | 2 +-
6 files changed, 9 insertions(+), 9 deletions(-)