Fix typo and example in comment/KB for `setval()`

sql/item_func.cc

@@ -6906,9 +6906,9 @@ longlong Item_func_lastval::val_int()
 /*
   Sets next value to be returned from sequences
 
-  SELECT setval('foo', 42, 0);           Next nextval will return 43
-  SELECT setval('foo', 42, 0, true);     Same as above
-  SELECT setval('foo', 42, 0, false);    Next nextval will return 42
+  SELECT setval(foo, 42, 0);           Next nextval will return 43
+  SELECT setval(foo, 42, 0, true);     Same as above
+  SELECT setval(foo, 42, 0, false);    Next nextval will return 42
 */
 
 longlong Item_func_setval::val_int()

sql/sql_sequence.cc

@@ -176,7 +176,7 @@ void sequence_definition::store_fields(TABLE *table)
 
 
 /*
-  Check the sequence fields through seq_fields when createing a sequence.
+  Check the sequence fields through seq_fields when creating a sequence.
 
   RETURN VALUES
     false       Success