auxdisplay: fix use after free in lcd2s_i2c_remove()

The kfree() needs to be moved down a line to prevent a use after free.

Fixes: 8c9108d0 ("auxdisplay: add a driver for lcd2s character display")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>