block/virtio-blk: Fix memory leak from virtio_blk_zone_report

block/virtio-blk: Fix memory leak from virtio_blk_zone_report

This modification ensures that in scenarios where the buffer size is
insufficient for a zone report, the function will now properly set an
error status and proceed to a cleanup label, instead of merely
returning.

The following ASAN log reveals it:

==1767400==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 312 byte(s) in 1 object(s) allocated from:
    #0 0x64ac7b3280cd in malloc llvm/compiler-rt/lib/asan/asan_malloc_linux.cpp:129:3
    #1 0x735b02fb9738 in g_malloc (/lib/x86_64-linux-gnu/libglib-2.0.so.0+0x5e738)
    #2 0x64ac7d23be96 in virtqueue_split_pop hw/virtio/virtio.c:1612:12
    #3 0x64ac7d23728a in virtqueue_pop hw/virtio/virtio.c:1783:16
    #4 0x64ac7cfcaacd in virtio_blk_get_request hw/block/virtio-blk.c:228:27
    #5 0x64ac7cfca7c7 in virtio_blk_handle_vq hw/block/virtio-blk.c:1123:23
    #6 0x64ac7cfecb95 in virtio_blk_handle_output hw/block/virtio-blk.c:1157:5

Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Message-id: 20240404120040.1951466-1-zheyuma97@gmail.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
(cherry picked from commit bbdf9023665f409113cb07b463732861af63fb47)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>