Revert "genirq: fix handle_nested_irq for lazy disable"

This reverts commit 79c7830368eb7daf8d3bf753827ec2a69a17528f.
Revert "printk: Don't allow cpu to get console lock during hotplugging"

This reverts commit 02ba942f3a8241ee22fd39022b75162a52f7213f.
Revert "cpu-hotplug: Add the function 'cpu_hotplug_inprogress'"

This reverts commit a52d6b967a24a4e25788b8dcd83a59d882a25b61.