genirq: Provide edge_eoi flow handler

This is a replacment for the cell flow handler which is in the way of
cleanups. Must be selected to avoid general bloat.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig
index 00f2c03..72606ba 100644
--- a/kernel/irq/Kconfig
+++ b/kernel/irq/Kconfig
@@ -51,6 +51,10 @@
 config IRQ_PREFLOW_FASTEOI
        bool
 
+# Edge style eoi based handler (cell)
+config IRQ_EDGE_EOI_HANDLER
+       bool
+
 # Support forced irq threading
 config IRQ_FORCED_THREADING
        bool