nvme-pci: check kstrtoint() return value in queue_count_set()

This patch avoids that the compiler complains about 'ret' being set
but not being used when building with W=1.

Fixes: 3b6592f ("nvme: utilize two queue maps, one for reads and one for writes") # v5.0-rc1
Signed-off-by: Bart Van Assche <[email protected]>
Reviewed-by: Sagi Grimberg <[email protected]>
Reviewed-by: Chaitanya Kulkarni <[email protected]>
Signed-off-by: Christoph Hellwig <[email protected]>
(cherry picked from commit e895fed)

Conflicts:
	drivers/nvme/host/pci.c

Orabug: 29933720

Signed-off-by: Alan Adamson <[email protected]>
Reviewed-by: John Donnelly <[email protected]>

Author: bvanassche

drivers/nvme/host/pci.c

@@ -135,6 +135,19 @@ static int io_queue_depth_set(const char *val, const struct kernel_param *kp)
 	return param_set_int(val, kp);
 }
 
+static int queue_count_set(const char *val, const struct kernel_param *kp)
+{
+	int n = 0, ret;
+
+	ret = kstrtoint(val, 10, &n);
+	if (ret)
+		return ret;
+	if (n > num_possible_cpus())
+		n = num_possible_cpus();
+
+	return param_set_int(val, kp);
+}
+
 static inline unsigned int sq_idx(unsigned int qid, u32 stride)
 {
 	return qid * 2 * stride;