pgsql: Fix duplication in ALTER MATERIALIZE VIEW synopsis

Fix duplication in ALTER MATERIALIZE VIEW synopsis

Commit 3c4cf080879b should have removed SET TABLESPACE from the synopsis
of ALTER MATERIALIZE VIEW as a possible "action" when it added a
separate line for it in the main command listing, but failed to.
Repair.

Backpatch to 9.4, like the aforementioned commit.

Branch
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REL9_5_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/f16159ce15040b0dc0b2c01b8c7345bfc594cc28

Modified Files
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doc/src/sgml/ref/alter_materialized_view.sgml | 1 -
1 file changed, 1 deletion(-)