Add define to allow multipart ccm to work

Add (internal only) define to config.h which allows the temporary
implementation of CCM to work, by removing the buffer zeroization on tag
fail when decrypting. This will obviously be removed when multipart CCM
is properaly implemented

Signed-off-by: Paul Elliott <paul.elliott@arm.com>
diff --git a/include/mbedtls/config.h b/include/mbedtls/config.h
index a4479d7..6cb05e4 100644
--- a/include/mbedtls/config.h
+++ b/include/mbedtls/config.h
@@ -3756,6 +3756,14 @@
  */
 //#define MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED
 
+/**
+ * Internal define that removes the zeroization of the output when decrypting
+ * CCM and the tag check fails. This is for internal use only, and was added so
+ * that PSA multipart CCM could be implmented. This option will be removed at
+ * some point in the future when proper CCM multipart support is implemented.
+ * Use at own risk.
+ */
+//#define MBEDTLS_INTERNAL_CCM_NO_ZEROIZE_ON_TAG_FAIL
 /* \} name SECTION: Customisation configuration options */
 
 /* Target and application specific configurations