iotests 60: more accurate set dirty bit in qcow2 header

Don't touch other incompatible bits, like compression-type. This makes
the test pass with IMGOPTS='compression_type=zstd'.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20211223160144.1097696-18-vsementsov@virtuozzo.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
diff --git a/tests/qemu-iotests/060 b/tests/qemu-iotests/060
index d1e3204..df87d60 100755
--- a/tests/qemu-iotests/060
+++ b/tests/qemu-iotests/060
@@ -326,7 +326,7 @@
 # Let the refblock appear unaligned
 poke_file "$TEST_IMG" "$rt_offset"        "\x00\x00\x00\x00\xff\xff\x2a\x00"
 # Mark the image dirty, thus forcing an automatic check when opening it
-poke_file "$TEST_IMG" 72 "\x00\x00\x00\x00\x00\x00\x00\x01"
+$PYTHON qcow2.py "$TEST_IMG" set-feature-bit incompatible 0
 # Open the image (qemu should refuse to do so)
 $QEMU_IO -c close "$TEST_IMG" 2>&1 | _filter_testdir | _filter_imgfmt