clk: renesas: Add r8a7742 CPG Core Clock Definitions

Add all RZ/G1H Clock Pulse Generator Core Clock Outputs, as listed in
Table 7.2a ("List of Clocks [RZ/G1H]") of the RZ/G1 Hardware User's
Manual.

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/1587678050-23468-8-git-send-email-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>