arm64: dts: ls1028a: delete extraneous #interrupt-cells for ENETC RCIE

This specifier overrides the interrupt specifier with 3 cells from gic
(/interrupt-controller@6000000), but in fact ENETC is not an interrupt
controller, so the property is bogus.

Interrupts used by the children of the ENETC RCIE must use the full
3-cell specifier required by the GIC.

The issue has no functional consequence so there is no real reason to
port the patch to stable trees.

Fixes: 927d7f85 ("arm64: dts: fsl: ls1028a: Add PCI IERC node and ENETC endpoints")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Michael Walle <michael@walle.cc>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>