net: davicom: fix UAF in dm9000_drv_remove

net: davicom: fix UAF in dm9000_drv_remove

dm is netdev private data and it cannot be
used after free_netdev() call. Using dm after free_netdev()
can cause UAF bug. Fix it by moving free_netdev() at the end of the
function.

This is similar to the issue fixed in commit
ad297cd2db89 ("net: qcom/emac: fix UAF in emac_remove").

This bug is detected by our static analysis tool.

Fixes: cf9e60aa69ae ("net: davicom: Fix regulator not turned off on driver removal")
Signed-off-by: Chenyuan Yang <chenyuan0y@gmail.com>
CC: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://patch.msgid.link/20250123214213.623518-1-chenyuan0y@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>