dfu: free entities when parsing fails

dfu: free entities when parsing fails

When dfu_init_env_entities() fails part-way through, some entities may
have been added to dfu_list. These are only removed by dfu_free_entities().
If that function isn't called, those stale entities will still exist the
next time dfu_init_env_entities() is called, leading to confusion. Fix
do_dfu() to ensure that dfu_free_entities() is always called, to avoid
this confusion.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Lukasz Majewski <l.majewski@samsung.com>
Tested-by: Lukasz Majewski <l.majewski@samsung.com>