tile: Update comments for generic idle conversion

As of commit 0dc8153cfebac68c9523b8852b14f10b31209f08 ("tile: Use generic
idle loop"), this applies to arch_cpu_idle() instead of cpu_idle().

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
1 file changed