lib.rs: Replace removed private_in_public rule

The private_in_public rule has been replaced with three other lints:

 * private_interfaces
 * private_bounds
 * renamed_and_removed_lints

Please refer to
https://rust-lang.github.io/rfcs/2145-type-privacy.html
for more information.

Signed-off-by: Tomás González <tomasagustin.gonzalezorlando@arm.com>

Author: tgonzalezorlandoarm

src/lib.rs

@@ -15,7 +15,9 @@
     overflowing_literals,
     path_statements,
     patterns_in_fns_without_body,
-    private_in_public,
+    private_bounds,
+    private_interfaces,
+    renamed_and_removed_lints,
     trivial_casts,
     trivial_numeric_casts,
     unconditional_recursion,