pgsql: pg_restore: Improve --help synopsis

pg_restore: Improve --help synopsis

The --help synopsis should only be one line. This rephrases the first
line a bit to reflect the new functionality of restoring multiple
databases from pg_dumpall output. Additional explanations are better
kept in the man page.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/15b1b4dd3fccfd2576f44841863153c312de011b

Modified Files
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src/bin/pg_dump/pg_restore.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)