do not pass NULL to strdup.

Also use qemu_strdup() instead of strdup() in bootindex code.

Signed-off-by: Gleb Natapov <[email protected]>
Signed-off-by: Aurelien Jarno <[email protected]>
diff --git a/vl.c b/vl.c
index 655617f..ed2cdfa 100644
--- a/vl.c
+++ b/vl.c
@@ -738,7 +738,7 @@
 
     node = qemu_mallocz(sizeof(FWBootEntry));
     node->bootindex = bootindex;
-    node->suffix = strdup(suffix);
+    node->suffix = suffix ? qemu_strdup(suffix) : NULL;
     node->dev = dev;
 
     QTAILQ_FOREACH(i, &fw_boot_order, link) {
@@ -785,7 +785,7 @@
         } else if (devpath) {
             bootpath = devpath;
         } else {
-            bootpath = strdup(i->suffix);
+            bootpath = qemu_strdup(i->suffix);
             assert(bootpath);
         }