pgsql: Propagate system identifier generation improvement into pg_reset

Propagate system identifier generation improvement into pg_resetxlog.

Commit 5035701e07e8bd395aa878465a102afd7b74e8c3 improved xlog.c's method
for creating a database system identifier, but I neglected to fix the
copy of that code appearing in pg_resetxlog.c.  Spotted by Andres Freund.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/4bcb3946249cbeed157ffd545a804913cfce749b

Modified Files
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src/bin/pg_resetxlog/pg_resetxlog.c |    3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)