ipq40xx: fix GL.iNet GL-B1300 support

ipq40xx: fix GL.iNet GL-B1300 support

Rename the dts file to match the used SoC type and drop the unnecessary
KERNEL_INSTALL from the image build code.

Remove the fixed rootfs and kernel partitions and create an image with
rootfs appended after kernel.

Setup a switch portmap matching the hardware and a default network/switch
configuration to make make the second lan port working. Use eth0 as lan
to have it consistent accross the target.

Use the power LED to indicate the boot status.

Sort the SoC entries within the dts by address and use dtc labels
whenever possible.

Signed-off-by: Mathias Kresin <dev@kresin.me>
Signed-off-by: Piotr Dymacz <pepe2k@gmail.com>