* Aspeed KCS (Keyboard Controller Style) IPMI interface

The Aspeed SOCs (AST2400 and AST2500) are commonly used as BMCs
(Baseboard Management Controllers) and the KCS interface can be
used to perform in-band IPMI communication with their host.

Required properties:
- compatible : should be one of
    "aspeed,ast2400-kcs-bmc"
    "aspeed,ast2500-kcs-bmc"
- interrupts : interrupt generated by the controller
- kcs_chan : The LPC channel number in the controller
- kcs_addr : The host CPU IO map address


Example:

    kcs3: kcs3@0 {
        compatible = "aspeed,ast2500-kcs-bmc";
        reg = <0x0 0x80>;
        interrupts = <8>;
        kcs_chan = <3>;
        kcs_addr = <0xCA2>;
        status = "okay";
    };