pgsql: Remove statement that to_char(interval) is deprecated; seems we

Log Message:
-----------
Remove statement that to_char(interval) is deprecated; seems we are
going to keep it after all.

Modified Files:
--------------
pgsql/doc/src/sgml:
func.sgml (r1.281 -> r1.282)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/func.sgml.diff?r1=1.281&r2=1.282)