dt-bindings: interrupt-controller: arm,gic: Correct VGIC interrupt description

dt-bindings: interrupt-controller: arm,gic: Correct VGIC interrupt description

The description of VGIC interrupt referenced obsolete "see below" after
converting TXT to DT Schema in commit 66ed144f147a ("dt-bindings:
interrupt-controller: Convert ARM GIC to json-schema"), because there is
no dedicated "VGIC" chapter anymore below.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Marc Zyngier <maz@kernel.org>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20241217061226.14139-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>