Register crypto hwmod links only if they are not disabled in DT.
If DT information is missing, enable them only for GP devices.

Before this patch crypto hwmod links were always disabled for all HS
devices and it was not possible to use omap-aes and omap-sham linux
drivers.
Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
[paul@pwsan.com: move the complex IP-block presence heuristics into their
 own function to simplify the code; fix some checkpatch warnings]
Signed-off-by: Paul Walmsley <paul@pwsan.com>