Обсуждение: pgsql: Fix documentation for shmem_startup_hook.

Fix documentation for shmem_startup_hook.

This section claims that each backend executes the
shmem_startup_hook shortly after attaching to shared memory, which
is true for EXEC_BACKEND builds, but not for others.  This commit
adds this important detail.

Oversight in commit 964152c476.

Reported-by: Sami Imseih <samimseih@gmail.com>
Reviewed-by: Sami Imseih <samimseih@gmail.com>
Discussion: https://postgr.es/m/CAA5RZ0vEGT1eigGbVt604LkXP6mUPMwPMxQoRCbFny44w%2B9EUQ%40mail.gmail.com
Backpatch-through: 17

Branch
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REL_17_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/778f391c26c6c569b3078daff1ac8e218024e46c

Modified Files
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doc/src/sgml/xfunc.sgml | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)