IB/qib: Fix txselect regression

Commit 7fac330("IB/qib: checkpatch fixes") was overzealous in
removing a simple_strtoul for a parse routine, setup_txselect().  That
routine is required to handle a multi-value string.

Unwind that aspect of the fix.

Cc: <stable@vger.kernel.org>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

drivers/infiniband/hw/qib/qib_iba7322.c

@@ -6190,21 +6190,20 @@ static int setup_txselect(const char *str, struct kernel_param *kp)
 {
 	struct qib_devdata *dd;
 	unsigned long val;
-	int ret;
-
+	char *n;
 	if (strlen(str) >= MAX_ATTEN_LEN) {
 		pr_info("txselect_values string too long\n");
 		return -ENOSPC;
 	}
-	ret = kstrtoul(str, 0, &val);
-	if (ret || val >= (TXDDS_TABLE_SZ + TXDDS_EXTRA_SZ +
+	val = simple_strtoul(str, &n, 0);
+	if (n == str || val >= (TXDDS_TABLE_SZ + TXDDS_EXTRA_SZ +
 				TXDDS_MFG_SZ)) {
 		pr_info("txselect_values must start with a number < %d\n",
 			TXDDS_TABLE_SZ + TXDDS_EXTRA_SZ + TXDDS_MFG_SZ);
-		return ret ? ret : -EINVAL;
+		return -EINVAL;
 	}
-
 	strcpy(txselect_list, str);
+
 	list_for_each_entry(dd, &qib_dev_list, list)
 		if (dd->deviceid == PCI_DEVICE_ID_QLOGIC_IB_7322)
 			set_no_qsfp_atten(dd, 1);