ARM: shmobile: lager: add gpio/fixed regulator for SDHI

Fixed regulator is used for SDHI0/2 Vcc.
We should use da9063 driver for Vccq,
but, it doesn't have regulator support at this point.
This patch uses gpio-regulator for it as quick-hack.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>