media: meson-ir-tx: Drop usage of platform_driver_probe()

The benefit of platform_driver_probe() here is only that the probe
function can be discarded after the driver is loaded. For an ARCH=arm
allmodconfig that's 952 bytes, for an allnoconfig + IR_MESON_TX=y it's
only 452 bytes. The downside is that the driver isn't dynamically
bindable and unbindable.

There are considerations to drop platform_driver_probe() as a concept
that isn't relevant any more today. It comes with an added complexity
that makes many users hold it wrong. (E.g. this driver didn't benefit
as much as it could as of v6.6-rc1 as meson_irtx_remove() could have
been marked with __exit.)

The advantages are not that relevant any more today, so convert this
driver to an ordinary platform driver.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>