lantiq: add Allnet ALL0333CJ support

lantiq: add Allnet ALL0333CJ support

This patch adds support for the Allnet ADSL2+ Modem ALL0333CJ.

Specifications:
- SoC: Amazon-SE
- RAM: 16MB
- Storage: 4MB NOR FLash
- LEDs: Power, Ethernet, DSL (Sync)
- Buttons: 1x Reset Button (not currently supported, will be done)
- 1x Ethernet-Port: 1x RJ45 10/100BaseTX
- 1x WAN-Port: AnnexB & J, G.992.1(ADSL), G.992.3(ADSL2), G.992.5(ADSL2+)

Installation:
- can be done via telnet+tftp or serial console
- default passwords:
  - via telnet (root:admin)
  - via webinterface http://172.16.1.254:8235/ (admin:coolwhite)

Installation via telnet / tftp:
host: # your own host must have an tftpd daemon, then do this:
host: ifconfig eth0:172 172.16.1.1 up
host: # telnet to allnet modem, root:admin
host: telnet 172.16.1.254
modem: # kill this daemon, it spams your console
modem: killall dsl_cpe_control
modem: # change to some place in ram:
modem: cd /ramdisk/tftp_upload
modem: # load lede-lantiq-ase-ALL0333CJ-squashfs-sysupgrade.bin alias uImage
modem: tftp -g -r uImage 172.16.1.1
modem: # load these extra tools from your tftpd via:
modem: # source: https://github.com/mcmilk/uboot-utils/releases/download/0.1/mips32.tar.gz
modem: tftp -g -r flashwrite 172.16.1.1
modem: tftp -g -r fw_setenv 172.16.1.1
modem: tftp -g -r fw.conf 172.16.1.1
modem: ln -s fw_setenv fw_printenv
modem: chmod +x *
modem: ./fw_setenv disable_recovery y
modem: ./fw_setenv kernel_addr 0xb0010000
modem: ./flashwrite /dev/mtd/1 uImage 0

Installation via serial line at uboot:
uboot: # erase everything exept bootloader
uboot: protect on b0000000 +10000; protect on b03f0000 +10000
uboot: erase all
uboot: # get new firmware via tftp:
uboot: tftpboot 0x80100000 uImage; setenv kernel_addr 0xb0010000
uboot: # copy to flash:
uboot: cp.b 0x80100000 $(kernel_addr) $(filesize)
uboot: # disable proprietary image checking:
uboot: setenv disable_recovery=y; saveenv
uboot: # reboot with LEDE ;)
uboot: reset

Ethernet works as expected, DSL syncronization does not work properly
currently, I am working on this issue.

Signed-off-by: Tino Reichardt <milky-lede@mcmilk.de>