wan/fsl_ucc_hdlc: use IS_ERR_VALUE() to check return value of qe_muram_alloc

qe_muram_alloc return a unsigned long integer,which should not
compared with zero. check it using IS_ERR_VALUE() to fix this.

Fixes: c19b6d24 ("drivers/net: support hdlc function for QE-UCC")
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/wan/fsl_ucc_hdlc.c

@@ -192,7 +192,7 @@ static int uhdlc_init(struct ucc_hdlc_private *priv)
 	priv->ucc_pram_offset = qe_muram_alloc(sizeof(struct ucc_hdlc_param),
 				ALIGNMENT_OF_UCC_HDLC_PRAM);
 
-	if (priv->ucc_pram_offset < 0) {
+	if (IS_ERR_VALUE(priv->ucc_pram_offset)) {
 		dev_err(priv->dev, "Can not allocate MURAM for hdlc parameter.\n");
 		ret = -ENOMEM;
 		goto free_tx_bd;
@@ -230,14 +230,14 @@ static int uhdlc_init(struct ucc_hdlc_private *priv)
 
 	/* Alloc riptr, tiptr */
 	riptr = qe_muram_alloc(32, 32);
-	if (riptr < 0) {
+	if (IS_ERR_VALUE(riptr)) {
 		dev_err(priv->dev, "Cannot allocate MURAM mem for Receive internal temp data pointer\n");
 		ret = -ENOMEM;
 		goto free_tx_skbuff;
 	}
 
 	tiptr = qe_muram_alloc(32, 32);
-	if (tiptr < 0) {
+	if (IS_ERR_VALUE(tiptr)) {
 		dev_err(priv->dev, "Cannot allocate MURAM mem for Transmit internal temp data pointer\n");
 		ret = -ENOMEM;
 		goto free_riptr;