clk: renesas: r9a07g044: Add M3 Clock support

Add support for M3 clock which is sourced from DSI divider connected
to PLL5_4 mux.

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/r/20220430114156.6260-7-biju.das.jz@bp.renesas.com


Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>