pgsql: pg_upgrade: report database names with missing extension libs

pg_upgrade: report database names with missing extension libs

Previously only the missing library name was reported, forcing users to
look in all databases to find the library entries.

Discussion: /messages/by-id/20180713162815.GA3835@momjian.us

Author: Daniel Gustafsson, me

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/60e3bd1d7f92430b24b710ecf0559656eb8ed499

Modified Files
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src/bin/pg_upgrade/function.c | 158 ++++++++++++++++++++--------------------
src/bin/pg_upgrade/pg_upgrade.h | 7 +-
2 files changed, 85 insertions(+), 80 deletions(-)