Important points:
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1. Works fine for pb926 + qemu.
2. Scan code logic for kryboard is not complete.
We just have generic keys and shift working.
3. Mouse scancodes are collected but not decoded.
4. Right now we are doing enable_irq(), just before we go for waiting
again for new irqs. This is not correct but we had latency issues.
This needs to be fixed immediately.
5. Also it seems like the notify_clot count should be an atomic
variable. Needs to be discussed.