ANDROID: irq/proc: use active cpus for allowed irq affinity

With the introduction of pause, irqs should avoid
paused cpus.  Previously, when userspace set the
irq affinity, it was only filtered toward online cpus.
A cpu can be paused but online, and irqs should avoid.

Check the cpu_active_mask instead of the online mask
when writing the irq affinity, such that the subset
of cpus allowed doesn't include inactive cpus.

Bug: 161210528
Change-Id: I359a452cc97ad58ad85e9613a29d144ffcd51567
Signed-off-by: Stephen Dickey <dickey@codeaurora.org>