MIPS: Alchemy: one kernel for DB1000/DB1500/DB1100

These 3 boards are very similar; with this patch a single kernel image
which runs on all three can be built.

Tested on DB1500 and DB1100.

Signed-off-by: Manuel Lauss <manuel.lauss@googlemail.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2872/


Signed-off-by: Ralf Baechle <ralf@linux-mips.org>