The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart from
emitting a warning).

To improve here there is a quest to make the remove callback return void.
In the first step of this quest all drivers are converted to .remove_new()
which already returns void. Eventually after all drivers are converted,
.remove_new() is renamed to .remove().

Before this driver might have returned an error. In this case emit a
warning that tells more about the problem than the generic warning by
the core, and instead of making the remove callback return zero
unconditionally, convert to .remove_new() which is equivalent.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Markus Schneider-Pargmann <msp@baylibre.com>
Link: https://lore.kernel.org/r/20230605161458.117361-1-u.kleine-koenig@pengutronix.deSigned-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>