freedreno/regs: define the wide bus enable bit in DSI_VID_CFG0
freedreno/regs: define the wide bus enable bit in DSI_VID_CFG0
Follow the kernel patch by Jonathan Marek and define the DATABUS_WIDEN bit in the DSI_VID_CFG0 register.
Since @flto doesn't seem to respond to comments at https://patchwork.freedesktop.org/patch/567521/, this defines corresponding register bit.