genirq: deprecate __do_IRQ

Two years migration time is enough. Remove the compability cruft.

Add the deprecated warning in kernel/irq/handle.c because marking
__do_IRQ itself is way too noisy.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index a2ee682..6661704 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -349,6 +349,11 @@
 }
 
 #ifndef CONFIG_GENERIC_HARDIRQS_NO__DO_IRQ
+
+#ifdef CONFIG_ENABLE_WARN_DEPRECATED
+# warning __do_IRQ is deprecated. Please convert to proper flow handlers
+#endif
+
 /**
  * __do_IRQ - original all in one highlevel IRQ handler
  * @irq:	the interrupt number