crypto: qat - change return value in adf_cfg_key_val_get()

If a key is not found in the internal key value storage, return -ENODATA
instead of -1 that is treated as -EPERM and may confuse.

Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>