The previous code assumed a channel has otg capability if a channel
has interrupt property. But, it is not good because:
- Battery charging feature also needs interrupt property.
- Some R-Car Gen3 SoCs (e.g. R-Car D3) doesn't have OTG capability.
So, this patch checks whether usb 2.0 host node has dr_mode property or[...]
not. If it has 'dr_mode = "otg";', this driver enables otg capability.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>