pgsql: Fix examples of how to use "su" while starting the server.

Fix examples of how to use "su" while starting the server.

The syntax "su -c 'command' username" is not accepted by all versions of
su, for example not OpenBSD's. More portable is "su username -c
'command'". So change runtime.sgml to recommend that syntax. Also,
add a -D switch to the OpenBSD example script, for consistency with other
examples. Per Denis Lapshin and Gábor Hidvégi.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/7d8cbeb0c3f48c6c204b742b6891a9e5e5031d15

Modified Files
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doc/src/sgml/runtime.sgml | 10 +++++-----
1 files changed, 5 insertions(+), 5 deletions(-)