ARM: imx6: fix regulator constraints on anatop 1p1 and 2p5

Fix the min/max voltage constraints for the anatop 1p1 and 2p5
regulator to match the typical operating range mentioned in the
datasheet.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>