imx: fdt: fix cooling-device property corruption

imx: fdt: fix cooling-device property corruption

The function disable_thermal_cpu_nodes() corrupts the cooling-device
property.
For example, booting an i.MX93 devices with only one A55 core (IMX93x1)
with the cooling-device property set to:

$ dtc -I dtb foo.dtb | grep cooling-device
cooling-device = <0x08 0xffffffff 0xffffffff 0x09 0xffffffff 0xffffffff>;

Linux shows the following error at boot:

[    1.715189] OF: /thermal-zones/cpu-thermal/cooling-maps/map0: could not find phandle 1083699869
[    1.723977] thermal_sys: Add a cooling_device property with at least one device
[    1.731285] thermal thermal_zone0: binding zone cpu-thermal with cdev thermal-devfreq-0 failed:-2

because the cooling-device property in the device tree passed to the
kernel is

$ dtc -I dtb /sys/firmware/fdt | grep cooling-device
cooling-device = <0x4097f29d 0x00 0xb05aef9d>;

The issue is because the wrong variable type is passed to the function
fdt_setprop() called in the function disable_thermal_cpu_nodes(). With
the variable type fixed, the error at boot is gone and the property is
properly set:

$ dtc -I dtb /sys/firmware/fdt | grep cooling-device
cooling-device = <0x08 0xffffffff 0xffffffff>;

Signed-off-by: Sébastien Szymanski <sebastien.szymanski@armadeus.com>