Make the newly-added regression tests for lo_truncate() consistent

with the recent largeobject cosmetic fixes. Jeremy Drake.

src/test/regress/input/largeobject.source

@@ -85,7 +85,7 @@ END;
 
 -- Test truncation.
 BEGIN;
-UPDATE lotest_stash_values SET fd=lo_open(loid, CAST((2 | 4) * 16^4 AS integer));
+UPDATE lotest_stash_values SET fd=lo_open(loid, CAST(x'20000' | x'40000' AS integer));
 
 SELECT lo_truncate(fd, 10) FROM lotest_stash_values;
 SELECT loread(fd, 15) FROM lotest_stash_values;

src/test/regress/output/largeobject.source

@@ -118,7 +118,7 @@ SELECT lo_close(fd) FROM lotest_stash_values;
 END;
 -- Test truncation.
 BEGIN;
-UPDATE lotest_stash_values SET fd=lo_open(loid, CAST((2 | 4) * 16^4 AS integer));
+UPDATE lotest_stash_values SET fd=lo_open(loid, CAST(x'20000' | x'40000' AS integer));
 SELECT lo_truncate(fd, 10) FROM lotest_stash_values;
  lo_truncate 
 -------------