ARM: OMAP2+: use true and false for bool variable

fixed the following coccicheck:
./arch/arm/mach-omap2/powerdomain.c:1205:9-10: WARNING: return of 0/1 in
function 'pwrdm_can_ever_lose_context' with return type bool

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>