pgsql: Improve pg_upgrade wording for pg_ctl start failure; could be

Improve pg_upgrade wording for pg_ctl start failure; could be
connection failure.

Backpatch to 9.2.

Per report from Evan D. Hoffman

Branch
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REL9_2_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/a88242067dc5f7e2e58a205a1ab7c8ee002d47fa

Modified Files
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contrib/pg_upgrade/server.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)