Add some checks on "char"-type columns to type_sanity and opr_sanity.

I noticed that the sanity checks in the regression tests omitted to
check a couple of "poor man's enum" columns that you'd reasonably
expect them to check.

There are other "char"-type columns in system catalogs that are not
covered by either type_sanity or opr_sanity, e.g. pg_rewrite.ev_type.
However, those catalogs are not populated with any manually-created
data during bootstrap, so it seems less necessary to check them
this way.

src/test/regress/expected/opr_sanity.out

@@ -57,7 +57,9 @@ WHERE p1.prolang = 0 OR p1.prorettype = 0 OR
        array_upper(p1.proargtypes, 1) != p1.pronargs-1 OR
        0::oid = ANY (p1.proargtypes) OR
        procost <= 0 OR
-       CASE WHEN proretset THEN prorows <= 0 ELSE prorows != 0 END;
+       CASE WHEN proretset THEN prorows <= 0 ELSE prorows != 0 END OR
+       provolatile NOT IN ('i', 's', 'v') OR
+       proparallel NOT IN ('s', 'r', 'u');
  oid | proname 
 -----+---------
 (0 rows)

src/test/regress/expected/type_sanity.out

@@ -465,7 +465,9 @@ ORDER BY 1;
 -- Look for illegal values in pg_class fields
 SELECT p1.oid, p1.relname
 FROM pg_class as p1
-WHERE p1.relkind NOT IN ('r', 'i', 's', 'S', 'c', 't', 'v', 'f');
+WHERE relkind NOT IN ('r', 'i', 's', 'S', 'c', 't', 'v', 'f') OR
+    relpersistence NOT IN ('p', 'u', 't') OR
+    relreplident NOT IN ('d', 'n', 'f', 'i');
  oid | relname 
 -----+---------
 (0 rows)

src/test/regress/sql/opr_sanity.sql

@@ -64,7 +64,9 @@ WHERE p1.prolang = 0 OR p1.prorettype = 0 OR
        array_upper(p1.proargtypes, 1) != p1.pronargs-1 OR
        0::oid = ANY (p1.proargtypes) OR
        procost <= 0 OR
-       CASE WHEN proretset THEN prorows <= 0 ELSE prorows != 0 END;
+       CASE WHEN proretset THEN prorows <= 0 ELSE prorows != 0 END OR
+       provolatile NOT IN ('i', 's', 'v') OR
+       proparallel NOT IN ('s', 'r', 'u');
 
 -- prosrc should never be null or empty
 SELECT p1.oid, p1.proname

src/test/regress/sql/type_sanity.sql

@@ -339,7 +339,9 @@ ORDER BY 1;
 
 SELECT p1.oid, p1.relname
 FROM pg_class as p1
-WHERE p1.relkind NOT IN ('r', 'i', 's', 'S', 'c', 't', 'v', 'f');
+WHERE relkind NOT IN ('r', 'i', 's', 'S', 'c', 't', 'v', 'f') OR
+    relpersistence NOT IN ('p', 'u', 't') OR
+    relreplident NOT IN ('d', 'n', 'f', 'i');
 
 -- Indexes should have an access method, others not.