pgsql: doc: Fix name of CRC algorithm in "Reliability" section.

doc: Fix name of CRC algorithm in "Reliability" section.

This section claims we use CRC-32 for WAL records and two-phase
state files, but we've actually used CRC-32C since v9.5 (commit
5028f22f6e).  Fix that.

Reviewed-by: Robert Haas
Discussion: https://postgr.es/m/ZrUFpLP-w2zTAHqq%40nathan
Backpatch-through: 12

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/8c3548613d7e2a7c010360e6f55fa6db849eeef9

Modified Files
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doc/src/sgml/wal.sgml | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)