genirq: threaded irq handlers review fixups

Delta patch to address the review comments.

      - Implement warning when IRQ_WAKE_THREAD is requested and no
        thread handler installed
      - coding style fixes

Pointed-out-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index a4c1ab8..a3eb7ba 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -407,20 +407,17 @@
 	return ret;
 }
 
-static inline int irq_thread_should_run(struct irqaction *action)
-{
-	return test_and_clear_bit(IRQTF_RUNTHREAD, &action->thread_flags);
-}
-
 static int irq_wait_for_interrupt(struct irqaction *action)
 {
 	while (!kthread_should_stop()) {
 		set_current_state(TASK_INTERRUPTIBLE);
-		if (irq_thread_should_run(action)) {
+
+		if (test_and_clear_bit(IRQTF_RUNTHREAD,
+				       &action->thread_flags)) {
 			__set_current_state(TASK_RUNNING);
 			return 0;
-		} else
-			schedule();
+		}
+		schedule();
 	}
 	return -1;
 }
@@ -820,8 +817,8 @@
  *	@irq: Interrupt line to allocate
  *	@handler: Function to be called when the IRQ occurs.
  *		  Primary handler for threaded interrupts
- *      @thread_fn: Function called from the irq handler thread
- *                  If NULL, no irq thread is created
+ *	@thread_fn: Function called from the irq handler thread
+ *		    If NULL, no irq thread is created
  *	@irqflags: Interrupt type flags
  *	@devname: An ascii name for the claiming device
  *	@dev_id: A cookie passed back to the handler function