MIPS: Malta: Fixup reboot

Commit 10b6ea09 ("MIPS: Malta: Use syscon-reboot driver to reboot")
converted the Malta board to use the generic syscon-reboot driver to
handle reboots, but incorrectly used the value 0x4d rather than 0x42 as
the magic to write to the reboot register.

I also incorrectly believed that syscon/regmap would default to native
endianness, but this isn't the case. Force this by specifying with a
native-endian property in the devicetree.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fixes: 10b6ea09 ("MIPS: Malta: Use syscon-reboot driver to reboot")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Cc: linux-mips@linux-mips.org
Tested-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Maciej W. Rozycki <macro@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/14396/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/boot/dts/mti/malta.dts

@@ -84,12 +84,13 @@ board-config@3e0000 {
 	fpga_regs: system-controller@1f000000 {
 		compatible = "mti,malta-fpga", "syscon", "simple-mfd";
 		reg = <0x1f000000 0x1000>;
+		native-endian;
 
 		reboot {
 			compatible = "syscon-reboot";
 			regmap = <&fpga_regs>;
 			offset = <0x500>;
-			mask = <0x4d>;
+			mask = <0x42>;
 		};
 	};