pgsql: Allocate fresh memory for post_opts/exec_path

Allocate fresh memory for post_opts/exec_path

Instead of having read_post_opts() depend on the memory allocated for
the config file (which is now getting free'd), pg_strdup() for
post_opts and exec_path (similar to how it's being done elsewhere).

Noted by Thom Brown.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/dd917bb793b27f8c7616f0e64f9a119e8d98eb24

Modified Files
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src/bin/pg_ctl/pg_ctl.c |    4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)