Add phy-connection-type to gianfar nodes

The TSEC/eTSEC automatically detect their PHY interface type, unless
the type is RGMII-ID (RGMII with internal delay). In that situation,
it just detects RGMII. In order to fix this, we need to pass in rgmii-id
if that is the connection type.

Signed-off-by: Andy Fleming <[e-mail]>

Documentation/powerpc/booting-without-of.txt

···
       network device.  This is used by the bootwrapper to interpret
       MAC addresses passed by the firmware when no information other
       than indices is available to associate an address with a device.
+    - phy-connection-type : a string naming the controller/PHY interface type,
+      i.e., "mii" (default), "rmii", "gmii", "rgmii", "rgmii-id", "sgmii",
+      "tbi", or "rtbi".  This property is only really needed if the connection
+      is of type "rgmii-id", as all other connection types are detected by
+      hardware.
+
 
   Example:
 

arch/powerpc/boot/dts/mpc8641_hpcn.dts

···
 			interrupts = <1d 2 1e 2 22 2>;
 			interrupt-parent = <&mpic>;
 			phy-handle = <&phy0>;
+			phy-connection-type = "rgmii-id";
 		};
 
 		ethernet@25000 {
···
 			interrupts = <23 2 24 2 28 2>;
 			interrupt-parent = <&mpic>;
 			phy-handle = <&phy1>;
+			phy-connection-type = "rgmii-id";
 		};
 		
 		ethernet@26000 {
···
 			interrupts = <1F 2 20 2 21 2>;
 			interrupt-parent = <&mpic>;
 			phy-handle = <&phy2>;
+			phy-connection-type = "rgmii-id";
 		};
 
 		ethernet@27000 {
···
 			interrupts = <25 2 26 2 27 2>;
 			interrupt-parent = <&mpic>;
 			phy-handle = <&phy3>;
+			phy-connection-type = "rgmii-id";
 		};
 		serial@4500 {
 			device_type = "serial";