arm64: dts: renesas: r8a774c0: Fix cpu nodes style

We usually leave a space between "=" and the value of device
tree properties, but unfortunately that was overlooked for the
"clocks" property of cpu@0 and cpu@1.
This patch fixes the spacing with the "clocks" property of
cpu@0 and cpu@1.

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>