pgsql: Fix uninitialized slot array access during the upgrade.

Fix uninitialized slot array access during the upgrade.

Commit 29d0a77fa introduced fetching slot information from the old cluster
but didn't initialize the required array in all the code paths. So when
trying to access the array in verbose mode for the new cluster, it leads
to an uninitialized memory access.

Author: Vignesh C
Discussion: http://postgr.es/m/CALDaNm1tntGP5=CtMz=v+k3_PGv7kE9t6iWSgX-QiurAaFkhZw@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/a7db71ed2787e7dbf2c41473a2b7df2fcb55abd0

Modified Files
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src/bin/pg_upgrade/info.c | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)