arm64: dts: imx8qxp: Fix MU4_INT number

MU4_INT correct number is 180, while 179 is for MU3_INT.

Fixes: 3d91ba65 ("arm64: dts: imx: add imx8qxp support")
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>