MIPS: Lantiq: Add machtypes for lantiq eval kits

This patch adds mach specific code for the Lantiq EASY50712/50601 evaluation
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Signed-off-by: John Crispin <blogic@openwrt.org>
Signed-off-by: Ralph Hempel <ralph.hempel@lantiq.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2255/
Patchwork: https://patchwork.linux-mips.org/patch/2361/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>