tools/virtio: add dev_WARN_ONCE and is_vmalloc_addr stubs

Add dev_WARN_ONCE and is_vmalloc_addr stubs needed by virtio_ring.c.
is_vmalloc_addr stub always returns false - that's fine since it's
merely a sanity check.

Created using Cursor CLI.

Message-ID: <[e-mail]>
Acked-by: Jason Wang <[e-mail]>
Signed-off-by: Michael S. Tsirkin <[e-mail]>

tools/virtio/linux/kernel.h

···
 #include <linux/log2.h>
 #include <linux/types.h>
 #include <linux/overflow.h>
+#include <linux/limits.h>
 #include <linux/list.h>
 #include <linux/printk.h>
 #include <linux/bug.h>
···
 #define dev_err(dev, format, ...) fprintf (stderr, format, ## __VA_ARGS__)
 #define dev_warn(dev, format, ...) fprintf (stderr, format, ## __VA_ARGS__)
 #define dev_warn_once(dev, format, ...) fprintf (stderr, format, ## __VA_ARGS__)
+
+#define dev_WARN_ONCE(dev, condition, format...) \
+	WARN_ONCE(condition, format)
+
+static inline bool is_vmalloc_addr(const void *x)
+{
+	return false;
+}
 
 #define min(x, y) ({				\
 	typeof(x) _min1 = (x);			\