[media] smiapp: Use unlocked __v4l2_ctrl_modify_range()

Instead of modifying the control ranges directly by manipulating struct
v4l2_ctrl, use __v4l2_ctrl_modify_range() for the purpose.

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