tools/virtio: 64 bit features

Missed one place where vringh_test used
long to pass features. Fix it up to u64.

Signed-off-by: Michael S. Tsirkin <[e-mail]>

tools/virtio/vringh_test.c

···
 	return 1;
 }
 
-static int parallel_test(unsigned long features,
+static int parallel_test(u64 features,
 			 bool (*getrange)(struct vringh *vrh,
 					  u64 addr, struct vringh_range *r),
 			 bool fast_vringh)