pgsql: doc: Fix network_ops -> inet_ops in SpGiST operator class list

doc: Fix network_ops -> inet_ops in SpGiST operator class list

network_ops is an opclass family of SpGiST, and the opclass able to
work on the inet type is named inet_ops.

Oversight in 7a1cd52, that reworked the design of the table listing all
the operators available.

Reported-by: Laurence Parry
Reviewed-by: Tom Lane, David G. Johnston
Discussion: /messages/by-id/167458110639.2667300.14741268666497110766@wrigleys.postgresql.org
Backpatch-through: 14

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/d7c4830abb1867ca4fb83add2a5fac558f778b6a

Modified Files
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doc/src/sgml/spgist.sgml | 24 ++++++++++++------------
1 file changed, 12 insertions(+), 12 deletions(-)