event/cnxk: verify strdup return

[ upstream commit b4b3a7037b2cab4dc5d004ed0fb9ec1e5911334e ]

Add verify strdup return value logic.

Fixes: 38c2e32 ("event/cnxk: add option to control SSO HWGRP QoS")

Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>

drivers/event/cnxk/cnxk_eventdev.c

@@ -522,6 +522,9 @@ parse_qos_list(const char *value, void *opaque)
 	char *end = NULL;
 	char *f = s;
 
+	if (s == NULL)
+		return;
+
 	while (*s) {
 		if (*s == '[')
 			start = s;