powerpc/fsl: Add/update miscellaneous missing binding

Missing bindings were found on running checkpatch.pl on bsc9132
device tree. This patch add/update the following

- Add bindings for L2 cache controller
- Add bindings for memory controller
- Update bindings for USB controller
Signed-off-by: NHarninder Rai <harninder.rai@freescale.com>
Signed-off-by: NScott Wood <scottwood@freescale.com>

Documentation/devicetree/bindings/powerpc/fsl/l2cache.txt

+Freescale L2 Cache Controller
+
+L2 cache is present in Freescale's QorIQ and QorIQ Qonverge platforms.
+The cache bindings explained below are ePAPR compliant
+
+Required Properties:
+
+- compatible	: Should include "fsl,chip-l2-cache-controller" and "cache"
+		  where chip is the processor (bsc9132, npc8572 etc.)
+- reg		: Address and size of L2 cache controller registers
+- cache-size	: Size of the entire L2 cache
+- interrupts	: Error interrupt of L2 controller
+- cache-line-size : Size of L2 cache lines
+
+Example:
+
+	L2: l2-cache-controller@20000 {
+		compatible = "fsl,bsc9132-l2-cache-controller", "cache";
+		reg = <0x20000 0x1000>;
+		cache-line-size = <32>; // 32 bytes
+		cache-size = <0x40000>; // L2,256K
+		interrupts = <16 2 1 0>;
+	};

Documentation/devicetree/bindings/powerpc/fsl/mem-ctrlr.txt

+Freescale DDR memory controller
+
+Properties:
+
+- compatible	: Should include "fsl,chip-memory-controller" where
+		  chip is the processor (bsc9132, mpc8572 etc.), or
+		  "fsl,qoriq-memory-controller".
+- reg		: Address and size of DDR controller registers
+- interrupts	: Error interrupt of DDR controller
+
+Example 1:
+
+	memory-controller@2000 {
+		compatible = "fsl,bsc9132-memory-controller";
+		reg = <0x2000 0x1000>;
+		interrupts = <16 2 1 8>;
+	};
+
+
+Example 2:
+
+	ddr1: memory-controller@8000 {
+		compatible = "fsl,qoriq-memory-controller-v4.7",
+				"fsl,qoriq-memory-controller";
+		reg = <0x8000 0x1000>;
+		interrupts = <16 2 1 23>;
+	};

Documentation/devicetree/bindings/usb/fsl-usb.txt

@@ -8,7 +8,9 @@ and additions :
 Required properties :
  - compatible : Should be "fsl-usb2-mph" for multi port host USB
    controllers, or "fsl-usb2-dr" for dual role USB controllers
-   or "fsl,mpc5121-usb2-dr" for dual role USB controllers of MPC5121
+   or "fsl,mpc5121-usb2-dr" for dual role USB controllers of MPC5121.
+   Wherever applicable, the IP version of the USB controller should
+   also be mentioned (for eg. fsl-usb2-dr-v2.2 for bsc9132).
  - phy_type : For multi port host USB controllers, should be one of
    "ulpi", or "serial". For dual role USB controllers, should be
    one of "ulpi", "utmi", "utmi_wide", or "serial".