arm64: dts: r8a7795: Add CPUIdle support for all CPU core

commit 3c3b44c752c4eef9a29694f4262934445c5f5da9 from
git://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas-bsp.git



This patch enables CPUIdle (Core shutdown) support for R-Car H3.

Signed-off-by: Takeshi Kihara <takeshi.kihara.df@renesas.com>
Signed-off-by: Meng Li <Meng.Li@windriver.com>
Signed-off-by: Bruce Ashfield <bruce.ashfield@gmail.com>