ARM: OMAP2+: clockdomain: work on wkdep/sleepdep functions

Split the clkdm_(add|del)_(wk|sleep)dep() functions into lockless and
locking versions -- this will be needed in a subsequent patch.  Also,
while here, remove the leading underscore, since these are not
currently static functions.  And for functions that have
kerneldoc-style comment blocks, but which are missing the initial
'/**' tag, fix the tag to indicate that they are kerneldoc.

Signed-off-by: Paul Walmsley <paul@pwsan.com>