ARM: dts: imx6qdl-icore: Fix wrong reg_2p5 regulator node name

- in reg_2p5, fix regulator node name as regulator-2p5v
- remove exctra line

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>