drivers: sh: resume enabled clocks fix

Extend the SH / SH-Mobile ARM clock framework to only
resume clocks that have been enabled.

Without this fix divide-by-zero is triggering on sh7372
FSIDIV during system wide resume of Suspend-to-RAM.

Signed-off-by: Magnus Damm <damm@opensource.se>
Reviewed-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>