sh: Add documentation and integrate into docbook build.

This adds some preliminary docbook bits for SH, tying in to the few
interfaces that are exposed and that have adequate kerneldoc comments.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

Documentation/DocBook/Makefile

@@ -12,7 +12,7 @@ DOCBOOKS := wanbook.xml z8530book.xml mcabook.xml videobook.xml \
 	    kernel-api.xml filesystems.xml lsm.xml usb.xml kgdb.xml \
 	    gadget.xml libata.xml mtdnand.xml librs.xml rapidio.xml \
 	    genericirq.xml s390-drivers.xml uio-howto.xml scsi.xml \
-	    mac80211.xml debugobjects.xml
+	    mac80211.xml debugobjects.xml sh.xml
 
 ###
 # The build process is as follows (targets):