ramips: fix WLI-TX4-AG300N boot and network

Partition label "linux" prevents the root file system to be mounted at
boot time leading to a kernel panic. After changing it to "firmware",
the 2 uimage partitions "kernel", "rootfs" and squashfs "rootfs_data"
are correctly recognized.

The attached IP175C 10/100 MBit switch cannot connect to a link with
fixed 1000Mbit speed. The correct link speed is 100MBit. The switch
is detected and can be configured via mdio bus and should allow two
separable VLANs to be configured for the 4 available ports.

Signed-off-by: Yo Abe <abe.geel@gmail.com>
[picked from openwrt/PR#330]
Signed-off-by: Mathias Kresin <dev@kresin.me>

target/linux/ramips/dts/WLI-TX4-AG300N.dts

@@ -37,7 +37,7 @@
 		};
 
 		partition@50000 {
-			label = "linux";
+			label = "firmware";
 			reg = <0x50000 0x3b0000>;
 		};
 	};
@@ -96,7 +96,16 @@
 	mtd-mac-address = <&factory 0x4>;
 
 	port@0 {
-		mediatek,fixed-link = <1000 1 1 1>;
+		mediatek,fixed-link = <100 1 1 1>;
+	};
+
+	mdio-bus {
+		status = "okay";
+
+		phy0: ethernet-phy@0 {
+			phy-mode = "mii";
+			reg = <0>;
+		};
 	};
 };