Use #include <foo.h> instead of #include "foo.h" in most cases.

We rely on the include path to find many of these headers.  It
especially doesn't make sense to use #include "foo.h" for headers
in the top-level include directory.

lib/util/dup3.c

@@ -29,7 +29,7 @@
 #include <fcntl.h>
 #include <unistd.h>
 
-#include "sudo_compat.h"
+#include <sudo_compat.h>
 
 int
 sudo_dup3(int oldd, int newd, int flags)