Qualcomm SLIMBUS controller

Required properties:

 - reg : Offset and length of the register region(s) for the device
 - reg-names : Register region name(s) referenced in reg above
	 Required register resource entries are:
	 "slimbus_physical": Physical adderss of controller register blocks
	 "slimbus_bam_physical": Physical address of Bus Access Module (BAM)
				 for this controller
 - compatible : should be "qcom,slim-msm"
 - cell-index : SLIMBUS number used for this controller
 - interrupts : Interrupt numbers used by this controller
 - interrupt-names : Required interrupt resource entries are:
	"slimbus_irq" : Interrupt for SLIMBUS core
	"slimbus_bam_irq" : Interrupt for controller core's BAM

Optional property:
 - reg entry for slew rate : If slew rate control register is provided, this
	 entry should be used.
 - reg-name for slew rate: "slimbus_slew_reg"
 - qcom,min-clk-gear : Minimum clock gear at which this controller can be run
		 (range: 1-10)
		 Default value will be 1 if this entry is not specified
 - qcom,max-clk-gear: Maximum clock gear at which this controller can be run
		 (range: 1-10)
		 Default value will be 10 if this entry is not specified
Example:
	slim@fe12f000 {
		cell-index = <1>;
		compatible = "qcom,slim-msm";
		reg = <0xfe12f000 0x35000>,
		      <0xfe104000 0x20000>;
		reg-names = "slimbus_physical", "slimbus_bam_physical";
		interrupts = <0 163 0 0 164 0>;
		interrupt-names = "slimbus_irq", "slimbus_bam_irq";
		qcom,min-clk-gear = <10>;
	};
