arm64: dts: renesas: hihope-common: Remove "label" from LEDs

Remove "label" properties from the LEDs device tree nodes, since
we don't have nice labels on the PCB.

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>