MIPS: PowerTV: Provide cpu-feature-overrides.h

This will optimize fls() and __fls() to use CLZ throughout the kernel,
and any other optimizations that depend on constant cpu_has_* values
will also be used.

Signed-off-by: David VomLehn <dvomlehn@cisco.com>
Signed-off-by: Shinya Kuribayashi <skuribay@pobox.com>
To: David VomLehn <dvomlehn@cisco.com>
To: macro@linux-mips.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1452/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>