ARM: dts: imx6dl-yapp4: Configure the OLED display segment offset

The imx6dl-yapp4 platform uses a GE-LX012864FWPP3N0000 OLED display.
The display consist of a 128x64 OLED panel and a SSD1305 controller.

The OLED panel resolution is 128x64 but the built-in controller default
resolution is 132x64. To display properly a segment offset needs to be
configured.

Signed-off-by: Michal Vokáč <michal.vokac@ysoft.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>