genirq: Minor readablity improvement in irq_wake_thread()

genirq: Minor readablity improvement in irq_wake_thread()

exit_irq_thread() clears IRQTF_RUNTHREAD flag and drops the thread's bit in
desc->threads_oneshot then. The bit must not be set again in between and it
does not, since irq_wake_thread() sees PF_EXITING flag first and returns.

Due to above the order or checking PF_EXITING and IRQTF_RUNTHREAD flags in
irq_wake_thread() is important. This change just makes it more visible in the
source code.

Signed-off-by: Alexander Gordeev <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>