clk: renesas: r8a779h0: Add EtherAVB clocks

Add the module clocks used by the Ethernet AVB (EtherAVB-IF) blocks on
the Renesas R-Car V4M (R8A779H0) SoC.

Signed-off-by: Cong Dang <cong.dang.xn@renesas.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/a5b4252d9822ded3fd523bc35417306cae2ec2bd.1707661303.git.geert+renesas@glider.be