clk: renesas: r8a779{5|6|65}: Add TPU clock

This patch adds the TPU clock on the R-Car r8a7795/r8a7796/r8a77965
SoCs.

Signed-off-by: Cao Van Dong <cv-dong@jinso.co.jp>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>