[media] s5p-tv: Fix return value in sdo_probe() on error paths

Use proper return value test for clk_get() and devm_regulator_get()
functions and propagate any errors from the clock and the regulator
subsystem to the driver core. In two cases a proper error code is
now returned rather than 0.

Reported-by: Peter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>