fix: tinycrypt的hmac.c应该使用定长数组

src/bt/blehost/ext/tinycrypt/src/hmac.c

@@ -61,7 +61,7 @@ int tc_hmac_set_key(TCHmacState_t ctx, const uint8_t *key,
         return TC_CRYPTO_FAIL;
     }
 
-    const uint8_t dummy_key[key_size];
+    const uint8_t dummy_key[1024];
     struct tc_hmac_state_struct dummy_state;
 
     if(key_size <= TC_SHA256_BLOCK_SIZE) {