Add missing untested feature gates

src/policy.rs

@@ -1,5 +1,6 @@
 //! Enums representing key policies.
 
+#[cfg(feature = "untested")]
 use crate::{error::Error, serialization::Tlv};
 
 /// Specifies how often the PIN needs to be entered for access to the credential in a

src/serialization.rs

@@ -79,6 +79,7 @@ impl<'a> Tlv<'a> {
     }
 
     /// Writes a TLV to the given buffer.
+    #[cfg(feature = "untested")]
     pub(crate) fn write(buffer: &mut [u8], tag: u8, value: &[u8]) -> Result<usize, Error> {
         if buffer.len() < CB_OBJ_TAG_MIN {
             return Err(Error::SizeError);
@@ -98,6 +99,7 @@ impl<'a> Tlv<'a> {
     /// Writes a TLV to the given buffer.
     ///
     /// `value` is guaranteed to be called with a mutable slice of length `length`.
+    #[cfg(feature = "untested")]
     pub(crate) fn write_as<Gen>(
         buffer: &mut [u8],
         tag: u8,