Error 6114 when compiling DSDT

I want to use acpi-debug to properly map the keyboard, and it needed a patched DSDT.
and I get this compile error, anyone know how to patch this?

Method (MHCF, 1, NotSerialized) { P80H = 0x78 Local0 = Arg0 (Local0 & 0x20) // Error 6114 Result is not used, operator has no effect Local0 >>= 0x05 RMBT = Local0 Sleep (0x14) Return (Local0) } 

Thank you!