After DMA is complete, the omap_sham_finish_req function is called as
a part of the done_task tasklet. During this its atomic and any calls
to pm functions should not assume they wont sleep.

The patch replaces a call to pm_runtime_put_sync (which can sleep) with
pm_runtime_put thus fixing a kernel panic observed on AM33xx SoC during
SHA operation.

Tested on an AM33xx SoC device (beaglebone board).
To reproduce the problem, used the tcrypt kernel module as:
modprobe tcrypt sec=2 mode=403
Signed-off-by: Joel A Fernandes <joelagnel@ti.com>
Cc: David S. Miller <davem@davemloft.net>
Acked-by: Mark A. Greer <mgreer@animalcreek.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>