Add chflags(2) and fchflags(2) to Ustat.i3.

Index: m3/m3core/src/unix/freebsd-2/Ustat.i3
--- Ustat.i3.orig	Wed Mar 15 16:47:47 1995
+++ Ustat.i3	Thu Jul 10 18:41:32 1997
@@ -70,4 +70,26 @@
 
 <*EXTERNAL*> PROCEDURE fstat (fd: int;  buf: struct_stat_star): int;
 
+(* chflags, fchflags *)
+CONST
+  (* Definitions of flags stored in file flags word. *)
+  (* Super-user and owner changeable flags. *)
+  UF_SETTABLE  = 16_0000ffff;      (* mask of owner changeable flags *)
+  UF_NODUMP    = 16_00000001;      (* do not dump file *)
+  UF_IMMUTABLE = 16_00000002;      (* file may not be changed *)
+  UF_APPEND    = 16_00000004;      (* writes to file may only append *)
+  UF_OPAQUE    = 16_00000008;      (* directory is opaque wrt. union *)
+
+  (* Super-user changeable flags. *)
+  SF_SETTABLE  = 16_ffff0000;      (* mask of superuser changeable flags *)
+  SF_ARCHIVED  = 16_00010000;      (* file is archived *)
+  SF_IMMUTABLE = 16_00020000;      (* file may not be changed *)
+  SF_APPEND    = 16_00040000;      (* writes to file may only append *)
+
+<*EXTERNAL*>
+PROCEDURE chflags(path: char_star; flags: u_long): int;
+
+<*EXTERNAL*>
+PROCEDURE fchflags(fd: int; flags: u_long): int;
+
 END Ustat.