pgsql: doc: fix wrong tag used in create sequence manual.

doc: fix wrong tag used in create sequence manual.

In ref/create_sequence.sgml <literal> tag was used for nextval function name.
This should have been <function> tag.

Author: Noboru Saito
Discussion: https://postgr.es/m/CAAM3qnJTDFFfRf5JHJ4AYrNcqXgMmj0pbH0%2Bvm%3DYva%2BpJyGymA%40mail.gmail.com
Backpatch-through: 10

Branch
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REL_13_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/dc9ed21a4f4fc1da39c70935fc3dcd298b851542

Modified Files
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doc/src/sgml/ref/create_sequence.sgml | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)