pgsql: Simplify/clean up code for varlena types

Log Message:
-----------
Simplify/clean up code for varlena types

Modified Files:
--------------
    pgsql/contrib/btree_gist:
        btree_bit.c (r1.2 -> r1.3)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/btree_gist/btree_bit.c.diff?r1=1.2&r2=1.3)
        btree_bytea.c (r1.2 -> r1.3)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/btree_gist/btree_bytea.c.diff?r1=1.2&r2=1.3)
        btree_gist.sql.in (r1.11 -> r1.12)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/btree_gist/btree_gist.sql.in.diff?r1=1.11&r2=1.12)
        btree_numeric.c (r1.2 -> r1.3)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/btree_gist/btree_numeric.c.diff?r1=1.2&r2=1.3)
        btree_text.c (r1.3 -> r1.4)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/btree_gist/btree_text.c.diff?r1=1.3&r2=1.4)
        btree_utils_var.c (r1.5 -> r1.6)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/btree_gist/btree_utils_var.c.diff?r1=1.5&r2=1.6)