vmm, virtio-devices: Deny zero sector writes for autodetected raw images

If the disk image was autodetected to raw (not specified with image_type
= 0) then in the virtio-block subsystem generate errors for writes to
block 0 (treat as if read-only). This gives an immediate error vs using
the image implementations in the block subsystem.

Signed-off-by: Rob Bradford <rbradford@meta.com>

fuzz/fuzz_targets/block.rs

@@ -68,6 +68,7 @@ fuzz_target!(|bytes: &[u8]| -> Corpus {
         None,
         queue_affinity,
         true,
+        false,
     )
     .unwrap();