pgsql: Remove 'optimization' to skip resolve_symlinks() when the found

Log Message:
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Remove 'optimization' to skip resolve_symlinks() when the found
executable file isn't itself a symlink. We still need to run the
algorithm so that any directory symlinks in the path to the
executable are replaced by a true path. Noticed this on seeing
pg_config give me a completely wrong answer for --pkglibdir when
I called it through a symlink to the installation bindir.

Modified Files:
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pgsql/src/port:
exec.c (r1.34 -> r1.35)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/port/exec.c.diff?r1=1.34&r2=1.35)