pgsql: Use regression results float8-small-is-zero only for NetBSD <

Log Message:
-----------
Use regression results float8-small-is-zero only for NetBSD < 3.0.

Backpatch to 8.1.X.

Simon Burge

Modified Files:
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pgsql/src/test/regress:
resultmap (r1.80 -> r1.81)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/resultmap.diff?r1=1.80&amp;r2=1.81)