[PATCH] genirq: doc: add design documentation

Add docbook file - includes API documentation.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Documentation/DocBook/Makefile

@@ -10,7 +10,8 @@ DOCBOOKS := wanbook.xml z8530book.xml mcabook.xml videobook.xml \
 	    kernel-hacking.xml kernel-locking.xml deviceiobook.xml \
 	    procfs-guide.xml writing_usb_driver.xml \
 	    kernel-api.xml journal-api.xml lsm.xml usb.xml \
-	    gadget.xml libata.xml mtdnand.xml librs.xml rapidio.xml
+	    gadget.xml libata.xml mtdnand.xml librs.xml rapidio.xml \
+	    genericirq.xml
 
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 # The build process is as follows (targets):