pgsql: Fix stray references to SubscriptRef

Fix stray references to SubscriptRef

This type never existed.  SubscriptingRef was meant instead.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/2eaa45e3-efc5-4d75-b082-f8159f51445f%40eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/9790affcce032710c907aced834e968f2fc41bce

Modified Files
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contrib/hstore/hstore_subs.c      |  2 +-
src/backend/utils/adt/arraysubs.c |  2 +-
src/backend/utils/adt/jsonbsubs.c |  2 +-
src/include/nodes/subscripting.h  | 15 ++++++++-------
4 files changed, 11 insertions(+), 10 deletions(-)