Defining max length for credBlobs

Signed-off-by: Pol Henarejos <pol.henarejos@cttc.es>

src/fido/fido.h

@@ -78,6 +78,7 @@ extern void set_opts(uint8_t);
 #define MAX_CREDENTIAL_COUNT_IN_LIST 16
 #define MAX_CRED_ID_LENGTH        1024
 #define MAX_RESIDENT_CREDENTIALS  256
+#define MAX_CREDBLOB_LENGTH       128
 
 typedef struct known_app {
     const uint8_t *rp_id_hash;