pgsql: Fix obsolete mention of non-int64 support in CREATE SEQUENCE doc

Fix obsolete mention of non-int64 support in CREATE SEQUENCE documentation.

The old text explained what happened if we didn't have working int64
arithmetic.  Since that case has been explicitly rejected by configure
since 8.4.3, documenting it in the 9.x branches can only produce confusion.

Branch
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REL9_3_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/2730d7254c5f30c14509859e4353f3f7120151d9

Modified Files
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doc/src/sgml/ref/create_sequence.sgml |    5 +----
1 file changed, 1 insertion(+), 4 deletions(-)