ath10k: fix memory leak on caldata on error exit path

caldata is not being free'd on the error exit path, causing
a memory leak and data definitely should not be freed. Free
caldata instead of data.

Thanks to Kalle Valo for spotting that data should not be
free'd.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>