iotests: Make 191 work with qcow2 options

In order for 191 to work with an explicit refcount_bits or compat=0.10,
we should strip format-specific information from the output--and we can
do so by using _filter_img_info.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-id: 20171123020832.8165-17-mreitz@redhat.com
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

tests/qemu-iotests/191

@@ -45,7 +45,6 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.qemu
 
 _supported_fmt qcow2
-_unsupported_imgopts compat=0.10
 _supported_proto file
 _supported_os Linux
 
@@ -92,7 +91,7 @@ echo === Check that both top and top2 point to base now ===
 echo
 
 _send_qemu_cmd $h "{ 'execute': 'query-named-block-nodes' }" "^}" |
-    _filter_generated_node_ids | _filter_actual_image_size
+    _filter_generated_node_ids | _filter_actual_image_size | _filter_img_info
 
 _send_qemu_cmd $h "{ 'execute': 'quit' }" "^}"
 wait=1 _cleanup_qemu
@@ -140,7 +139,7 @@ echo === Check that both top and top2 point to base now ===
 echo
 
 _send_qemu_cmd $h "{ 'execute': 'query-named-block-nodes' }" "^}" |
-    _filter_generated_node_ids | _filter_actual_image_size
+    _filter_generated_node_ids | _filter_actual_image_size | _filter_img_info
 
 _send_qemu_cmd $h "{ 'execute': 'quit' }" "^}"
 wait=1 _cleanup_qemu