genirq: Add IRQ_INPROGRESS to core

We need to maintain the flag for now in both fields status and istate.
Add a CONFIG_GENERIC_HARDIRQS_NO_COMPAT switch to allow testing w/o
the status one. Wrap the access to status IRQ_INPROGRESS in a inline
which can be turned of with CONFIG_GENERIC_HARDIRQS_NO_COMPAT along
with the define.

There is no reason that anything outside of core looks at this. That
needs some modifications, but we'll get there.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig
index 4cd5d71..9e2256d 100644
--- a/kernel/irq/Kconfig
+++ b/kernel/irq/Kconfig
@@ -13,6 +13,9 @@
 config GENERIC_HARDIRQS_NO_DEPRECATED
        def_bool n
 
+config GENERIC_HARDIRQS_NO_COMPAT
+       def_bool n
+
 # Options selectable by the architecture code
 config HAVE_SPARSE_IRQ
        def_bool n