Merge catalog/pg_foo_fn.h headers back into pg_foo.h headers.

Traditionally, include/catalog/pg_foo.h contains extern declarations
for functions in backend/catalog/pg_foo.c, in addition to its function
as the authoritative definition of the pg_foo catalog's rowtype.
In some cases, we'd been forced to split out those extern declarations
into separate pg_foo_fn.h headers so that the catalog definitions
could be #include'd by frontend code.  That problem is gone as of
commit 9c0a0de, so let's undo the splits to make things less
confusing.

Discussion: https://postgr.es/m/23690.1523031777@sss.pgh.pa.us

Author: tglsfdc

contrib/sepgsql/dml.c

@@ -18,7 +18,7 @@
 #include "catalog/dependency.h"
 #include "catalog/pg_attribute.h"
 #include "catalog/pg_class.h"
-#include "catalog/pg_inherits_fn.h"
+#include "catalog/pg_inherits.h"
 #include "commands/seclabel.h"
 #include "commands/tablecmds.h"
 #include "executor/executor.h"

src/backend/catalog/dependency.c

@@ -27,11 +27,8 @@
 #include "catalog/pg_authid.h"
 #include "catalog/pg_cast.h"
 #include "catalog/pg_collation.h"
-#include "catalog/pg_collation_fn.h"
 #include "catalog/pg_constraint.h"
-#include "catalog/pg_constraint_fn.h"
 #include "catalog/pg_conversion.h"
-#include "catalog/pg_conversion_fn.h"
 #include "catalog/pg_database.h"
 #include "catalog/pg_default_acl.h"
 #include "catalog/pg_depend.h"

src/backend/catalog/heap.c

@@ -45,7 +45,6 @@
 #include "catalog/pg_attrdef.h"
 #include "catalog/pg_collation.h"
 #include "catalog/pg_constraint.h"
-#include "catalog/pg_constraint_fn.h"
 #include "catalog/pg_foreign_table.h"
 #include "catalog/pg_inherits.h"
 #include "catalog/pg_namespace.h"
@@ -55,7 +54,6 @@
 #include "catalog/pg_subscription_rel.h"
 #include "catalog/pg_tablespace.h"
 #include "catalog/pg_type.h"
-#include "catalog/pg_type_fn.h"
 #include "catalog/storage.h"
 #include "catalog/storage_xlog.h"
 #include "commands/tablecmds.h"

src/backend/catalog/index.c

@@ -41,9 +41,8 @@
 #include "catalog/pg_am.h"
 #include "catalog/pg_collation.h"
 #include "catalog/pg_constraint.h"
-#include "catalog/pg_constraint_fn.h"
 #include "catalog/pg_depend.h"
-#include "catalog/pg_inherits_fn.h"
+#include "catalog/pg_inherits.h"
 #include "catalog/pg_operator.h"
 #include "catalog/pg_opclass.h"
 #include "catalog/pg_tablespace.h"

src/backend/catalog/namespace.c

@@ -28,7 +28,6 @@
 #include "catalog/pg_authid.h"
 #include "catalog/pg_collation.h"
 #include "catalog/pg_conversion.h"
-#include "catalog/pg_conversion_fn.h"
 #include "catalog/pg_namespace.h"
 #include "catalog/pg_opclass.h"
 #include "catalog/pg_operator.h"

src/backend/catalog/objectaddress.c

@@ -30,7 +30,6 @@
 #include "catalog/pg_event_trigger.h"
 #include "catalog/pg_collation.h"
 #include "catalog/pg_constraint.h"
-#include "catalog/pg_constraint_fn.h"
 #include "catalog/pg_conversion.h"
 #include "catalog/pg_database.h"
 #include "catalog/pg_extension.h"

src/backend/catalog/partition.c

@@ -26,7 +26,6 @@
 #include "catalog/partition.h"
 #include "catalog/pg_collation.h"
 #include "catalog/pg_inherits.h"
-#include "catalog/pg_inherits_fn.h"
 #include "catalog/pg_opclass.h"
 #include "catalog/pg_partitioned_table.h"
 #include "catalog/pg_type.h"

src/backend/catalog/pg_aggregate.c

@@ -19,11 +19,9 @@
 #include "catalog/dependency.h"
 #include "catalog/indexing.h"
 #include "catalog/pg_aggregate.h"
-#include "catalog/pg_aggregate_fn.h"
 #include "catalog/pg_language.h"
 #include "catalog/pg_operator.h"
 #include "catalog/pg_proc.h"
-#include "catalog/pg_proc_fn.h"
 #include "catalog/pg_type.h"
 #include "miscadmin.h"
 #include "parser/parse_coerce.h"

src/backend/catalog/pg_collation.c

@@ -22,7 +22,6 @@
 #include "catalog/indexing.h"
 #include "catalog/objectaccess.h"
 #include "catalog/pg_collation.h"
-#include "catalog/pg_collation_fn.h"
 #include "catalog/pg_namespace.h"
 #include "mb/pg_wchar.h"
 #include "utils/builtins.h"

src/backend/catalog/pg_constraint.c

@@ -22,7 +22,6 @@
 #include "catalog/indexing.h"
 #include "catalog/objectaccess.h"
 #include "catalog/pg_constraint.h"
-#include "catalog/pg_constraint_fn.h"
 #include "catalog/pg_operator.h"
 #include "catalog/pg_type.h"
 #include "commands/defrem.h"