phy: tegra: xusb: Only warn once about reset problems in .remove()

The single difference between returning 0 and returning an error code in
a platform remove callback is that in the latter case the platform core
emits a warning about the error being ignored.

If reset_control_assert() fails there is already a warning, so suppress
the more generic (and less helpful) by returning 0 in
tegra_xusb_padctl_remove().

This is a preparation for making platform remove callbacks return void.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220716145403.107703-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>