pgsql: Fix overly-aggressive and inconsistent quoting in OS X start scr

Fix overly-aggressive and inconsistent quoting in OS X start script.

Sidar Lopez, per bug #6310, with some additional improvements by me.
Back-patch to 9.0, where the issue was introduced.

Branch
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REL9_0_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/87b0dcf490ffe2930940488b89ff94c62dd7153b

Modified Files
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contrib/start-scripts/osx/PostgreSQL | 12 ++++++------
1 files changed, 6 insertions(+), 6 deletions(-)