i2c: imx: move to generic GPIO recovery

Starting with
commit 75820314 ("i2c: core: add generic I2C GPIO recovery")
GPIO bus recovery is supported by the I2C core, so we can remove the
driver implementation and use that one instead.

As a nice side-effect, pinctrl becomes optional, allowing bus recovery on
LS1021A, which does not have such luxury, but can be wired up to use extra
fixed GPIO pins.

Note: The previous error messages about bus recovery not being supported is
dropped with this change. Given that it is perfectly possible to have platforms
where bus recovery works without pinctrl support, I happen to work on one such,
both error messages does not really make sense in those cases. And I don't see
how to know if this is the case or not.

Signed-off-by: Esben Haabendal <esben@geanix.com>
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>