ath10k: free cached fw bin contents when get board id fails

ath10k_core_probe_fw() simply returns error without freeing
cached firmware file content when get board id operation fails.
Free cached fw bin data in failure case to avoid memory leak.

Fixes: db0984e51a18 ("ath10k: select board data based on BMI chip id and board id")
Signed-off-by: Raja Mani <rmani@qti.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

drivers/net/wireless/ath/ath10k/core.c

@@ -1839,7 +1839,7 @@ static int ath10k_core_probe_fw(struct ath10k *ar)
 	if (ret && ret != -EOPNOTSUPP) {
 		ath10k_err(ar, "failed to get board id from otp: %d\n",
 			   ret);
-		return ret;
+		goto err_free_firmware_files;
 	}
 
 	ret = ath10k_core_fetch_board_file(ar);