ARM: dts: am437x-cm-t43: Fixup (again) tps65218 irq type

While the correct IRQ level fixed the WARN_ON(), but prevented the probe
of tps65218 as GIC_SPI does not support LEVEL_LOW (?)

Use LEVEL_HIGH as it looks to be the accurate one since the INTn of TPS is
connected to NMIn of the SoC.

Fixes: b997f534 ("ARM: dts: am437x-cm-t43: Correct tps65218 irq type")
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/boot/dts/am437x-cm-t43.dts

@@ -203,7 +203,7 @@ &i2c0 {
 	tps65218: tps65218@24 {
 		compatible = "ti,tps65218";
 		reg = <0x24>;
-		interrupts = <GIC_SPI 7 IRQ_TYPE_LEVEL_LOW>; /* NMIn */
+		interrupts = <GIC_SPI 7 IRQ_TYPE_LEVEL_HIGH>; /* NMIn */
 		interrupt-parent = <&gic>;
 		interrupt-controller;
 		#interrupt-cells = <2>;