MIPS: Use bool function return values of true/false not 1/0

Use the normal return values for bool functions

Signed-off-by: Joe Perches <joe@perches.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9640/


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