pgsql: Refactor BuildIndexInfo() with the new makeIndexInfo()

Refactor BuildIndexInfo() with the new makeIndexInfo()

This portion of the code got forgotten in 7cce159 which has introduced a
new routine to build this node, and this finishes the unification of the
places where IndexInfo is initialized.

Author: Michael Paquier
Discussion: /messages/by-id/20190801041322.GA3435@paquier.xyz

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/69edf4f8802247209e77f69e089799b3d83c13a4

Modified Files
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src/backend/catalog/index.c | 52 +++++++++++++--------------------------------
1 file changed, 15 insertions(+), 37 deletions(-)