ARM: dts: iwg20m: Correct indentation of mmcif0 properties

Fixes: 4658c4b789d8e2ae ("ARM: dts: iwg20m: Add MMCIF0 support")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Chris Paterson <chris.paterson2@renesas.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>