[media] smiapp: Access flash capabilities through limits

The flash capability register is already read as part of the limit
registers. Do no access it separately; instead use the value from the
limits.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>