crypto: keembay - Add missing check after sg_nents_for_len()

sg_nents_for_len() returns an int which is negative in case of error.

Fixes: 472b04444cd3 ("crypto: keembay - Add Keem Bay OCS HCU driver")
Signed-off-by: Thomas Fourier <[e-mail]>
Signed-off-by: Herbert Xu <[e-mail]>

drivers/crypto/intel/keembay/keembay-ocs-hcu-core.c

···
 	struct device *dev = rctx->hcu_dev->dev;
 	unsigned int remainder = 0;
 	unsigned int total;
-	size_t nents;
+	int nents;
 	size_t count;
 	int rc;
 	int i;
···
 
 	/* Determine the number of scatter gather list entries to process. */
 	nents = sg_nents_for_len(req->src, rctx->sg_data_total - remainder);
+
+	if (nents < 0)
+		return nents;
 
 	/* If there are entries to process, map them. */
 	if (nents) {