FROMLIST: virt: geniezone: Add ioeventfd support

Ioeventfd leverages eventfd to provide asynchronous notification
mechanism for VMM. VMM can register a mmio address and bind with an
eventfd. Once a mmio trap occurs on this registered region, its
corresponding eventfd will be notified.

Change-Id: Iff6bb7dd8ba42d08813e531ab40629492a1218bc
Signed-off-by: Yingshiuan Pan <yingshiuan.pan@mediatek.com>
Signed-off-by: Liju Chen <liju-clr.chen@mediatek.com>
Signed-off-by: Yi-De Wu <yi-de.wu@mediatek.com>
Bug: 280363874
Link: https://lore.kernel.org/lkml/20230727080005.14474-8-yi-de.wu@mediatek.com/