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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REL8_4_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/5ced7dc16d8baf37cc0d9ee3cb8f2df5dca64ed5

Modified Files
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doc/src/sgml/runtime.sgml | 8 ++++----
1 files changed, 4 insertions(+), 4 deletions(-)