dt-bindings: thermal: rcar-gen3-thermal: All variants use 3 interrupts

dt-bindings: thermal: rcar-gen3-thermal: All variants use 3 interrupts

RZ/G2M also has 3 interrupts routed to the TSC, but the list was not
updated to reflect this.

Just drop the list, as this is the case for this TSC variant in all
R-Car Gen3 and RZ/G2 SoCs.

Fixes: be6af481f3b2d508 ("dt-bindings: thermal: rcar-gen3-thermal: Add r8a774a1 support")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>