[PATCH] i2c: convert ds1374 to use a workqueue

A tasklet is not suitable for what the ds1374 driver does: neither sleeping
nor mutex operations are allowed in tasklets, and ds1374_set_tlet may do
both.

We can use a workqueue instead, where both sleeping and mutex operations
are allowed.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Randy Vinson <rvinson@mvista.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>