MIPS: Kconfig: Disable SMP/CPS for 64-bit

A 64-bit build for Malta produces far too many build problems
when SMP/CPS is selected. Moreover, there is currently no 64-bit
product with SMP/CPS so we disable SMP/CPS when building for
64-bit until it is properly supported.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8573/


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