MIPS: Alchemy: remove declaration for set_cpuspec

set_cpuspec() has been dropped with commit 074cf656
("MIPS: Alchemy: remove cpu_table.") in late 2008.

Signed-off-by: Manuel Lauss <manuel.lauss@gmail.com>
Cc: Linux-MIPS <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/9150/


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