pgsql: Fix warning introduced in 5c279a6d350.

Fix warning introduced in 5c279a6d350.

Change two macros to be static inline functions instead to keep the
data type consistent. This avoids a "comparison is always true"
warning that was occurring with -Wtype-limits. In the process, change
the names to look less like macros.

Discussion: https://postgr.es/m/20220407063505.njnnrmbn4sxqfsts@alap3.anarazel.de

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/9553b4115f1879f66935f42fff0b798ef91866d0

Modified Files
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src/backend/access/transam/rmgr.c | 4 ++--
src/backend/access/transam/xlogreader.c | 2 +-
src/bin/pg_waldump/pg_waldump.c | 6 +++---
src/bin/pg_waldump/rmgrdesc.c | 4 ++--
src/include/access/rmgr.h | 18 ++++++++++++++----
5 files changed, 22 insertions(+), 12 deletions(-)