pgsql: Retain relkind too in RTE_SUBQUERY entries for views.

Retain relkind too in RTE_SUBQUERY entries for views.

47bb9db75 modified the ApplyRetrieveRule()'s conversion of a view's
original RTE_RELATION entry into an RTE_SUBQUERY one to retain relid,
rellockmode, and perminfoindex so that the executor can lock the view
and check its permissions. It seems better to also retain
relkind for cross-checking that the exception of an
RTE_SUBQUERY entry being allowed to carry relation details only
applies to views, so do so.

Bump catversion because this changes the output format of
RTE_SUBQUERY RTEs.

Suggested-by: David Steele <david(at)pgmasters(dot)net>
Reviewed-by: David Steele <david(at)pgmasters(dot)net>
Reviewed-by: Álvaro Herrera <alvherre(at)alvh(dot)no-ip(dot)org>
Discussion: https://postgr.es/m/3953179e-9540-e5d1-a743-4bef368785b0%40pgmasters.net

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/0f8cfaf8921fed35f0b92d918ce95eec7b46ff05

Modified Files
--------------
src/backend/executor/execMain.c | 9 +++++++++
src/backend/nodes/outfuncs.c | 1 +
src/backend/nodes/readfuncs.c | 1 +
src/backend/rewrite/rewriteHandler.c | 7 +++----
src/include/catalog/catversion.h | 2 +-
src/include/nodes/parsenodes.h | 14 +++++++-------
6 files changed, 22 insertions(+), 12 deletions(-)