tools/virtio/ringtest: Remove bogus definition of BUG_ON()

BUG_ON(x) should raise an error if x is true, but assert(x) raises an
error if x is false. Remove this bogus definition of BUG_ON(), which
isn't used anyway.
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

tools/virtio/ringtest/ptr_ring.c

@@ -18,7 +18,6 @@
 #define ALIGN(x, a) (((x) + (a) - 1) / (a) * (a))
 #define SIZE_MAX        (~(size_t)0)
 #define KMALLOC_MAX_SIZE SIZE_MAX
-#define BUG_ON(x) assert(x)
 
 typedef pthread_spinlock_t  spinlock_t;