Documentation: update docs for mmp dt

Append interrupt controller and timer document for mmp. Updates
documents for gpio and i2c.

Signed-off-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>

Documentation/devicetree/bindings/i2c/mrvl-i2c.txt

@@ -3,34 +3,31 @@
 Required properties :
 
  - reg : Offset and length of the register set for the device
- - compatible : should be "mrvl,mmp-twsi" where CHIP is the name of a
+ - compatible : should be "mrvl,mmp-twsi" where mmp is the name of a
    compatible processor, e.g. pxa168, pxa910, mmp2, mmp3.
    For the pxa2xx/pxa3xx, an additional node "mrvl,pxa-i2c" is required
    as shown in the example below.
 
 Recommended properties :
 
- - interrupts : <a b> where a is the interrupt number and b is a
-   field that represents an encoding of the sense and level
-   information for the interrupt.  This should be encoded based on
-   the information in section 2) depending on the type of interrupt
-   controller you have.
+ - interrupts : the interrupt number
  - interrupt-parent : the phandle for the interrupt controller that
-   services interrupts for this device.
+   services interrupts for this device. If the parent is the default
+   interrupt controller in device tree, it could be ignored.
  - mrvl,i2c-polling : Disable interrupt of i2c controller. Polling
    status register of i2c controller instead.
  - mrvl,i2c-fast-mode : Enable fast mode of i2c controller.
 
 Examples:
 	twsi1: i2c@d4011000 {
-		compatible = "mrvl,mmp-twsi", "mrvl,pxa-i2c";
+		compatible = "mrvl,mmp-twsi";
 		reg = <0xd4011000 0x1000>;
 		interrupts = <7>;
 		mrvl,i2c-fast-mode;
 	};
 	
 	twsi2: i2c@d4025000 {
-		compatible = "mrvl,mmp-twsi", "mrvl,pxa-i2c";
+		compatible = "mrvl,mmp-twsi";
 		reg = <0xd4025000 0x1000>;
 		interrupts = <58>;
 	};