ARM: dts: r8a7742: Initial SoC device tree

The initial R8A7742 SoC device tree including CPU[0-8], PMU, PFC,
CPG, RST, SYSC, ICRAM[0-2], SCIFA2, MMC1, DMAC[0-1], GIC, PRR, timer
and the required clock descriptions.
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Marian-Cristian Rotariu <marian-cristian.rotariu.rb@bp.renesas.com>
Link: https://lore.kernel.org/r/1588542414-14826-7-git-send-email-prabhakar.mahadev-lad.rj@bp.renesas.comSigned-off-by: Geert Uytterhoeven <geert+renesas@glider.be>