pgsql: Refactor creation of normal dependency records when creating ext

Refactor creation of normal dependency records when creating extension

When creating an extension, the same type of dependency is used when
registering a dependency to a schema and required extensions. This
improves the code so as those dependencies are not recorded one-by-one,
but grouped together. Note that this has as side effect to remove
duplicate dependency entries, even if it should not happen in practice
as extensions listed as required in a control file should be listed only
once.

Extracted from a larger patch by the same author.

Author: Daniel Dustafsson
Discussion: https://postgr.es/m/20200629065535.GA183079@paquier.xyz

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/684b4f29b729e5b135d256802d6e712222b9551f

Modified Files
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src/backend/commands/extension.c | 24 ++++++++++++------------
1 file changed, 12 insertions(+), 12 deletions(-)