video: slimport: Fix the case of TV power off

When slimport is connected and TV is off.
slimport will keep seeking for hdmi connection and not notify it.
For the case of this, when connection lost,
Call power down and init, to initialize and wait for connection

Change-Id: I9bbf8b82d77ee69fb758adf8f1805fc88f17700a
Signed-off-by: Se Hun Kim <sean2.kim@lge.com>
video: slimport: Fix unblanced IRQ enable

If irq_enabled is set again, it causes the unblanced IRQ enable problem and
slimport would be not working properly. So if irq_enabled is set again,
In order to fix the problem, disable the irq and initialize the flags.

Change-Id: I27ad8ae7d553e515e15dd87744c221dbbb3a0717
Signed-off-by: Devin Kim <dojip.kim@lge.com>
video: slimport: Set/clear sp_tx_pd_mode in the power control function

sp_tx_pd_mode is the flag if tx power is down or not. So it should be
controlled in the power control function.

Change-Id: I394acbd6c6125dce8725aa81193b7be2abdf47b0
Signed-off-by: Devin Kim <dojip.kim@lge.com>
video: slimport: Do not access the sp registers after power down

The burst i2c errors sometimes causes a watchdog reset. The i2c errors
are caused by accessing the sp registers after SP is power down. So
do not access the sp register after power down to avoid the watchdog reset.

Change-Id: If64b0bf6f437292f356fa165d4203d522c26cfe6
Signed-off-by: Devin Kim <dojip.kim@lge.com>