MLK-17138: arm64: dts: sl-imx8qm.dtsi: Quad display support for 8QM

MLK-17138: arm64: dts: sl-imx8qm.dtsi: Quad display support for 8QM

Add DTS files fo quad display on 8QM boards. Currently, there is only
one file for this: fsl-imx8qm-lpddr4-arm2-it6263-adv7535.dts, which is
the combination for 2 LVDS + 2 MIPI-HDMI on LPDDR4 board.
This patch adds the other possible use-cases:
- 2 LVDS + 2 MIPI-Panel on LPDDR4
- 2 LVDS + 2 MIPI-HDMI on MEK
- 2 LVDS + 2 MIPI-Panel on MEK

Also:
- fix the fsl-imx8qm-lpddr4-arm2-it6263-adv7535.dts, since it
contained the old mipi_dsi nodes.
- fix the order of mipi_dsi nodes in fsl-imx8qm.dtsi, since this order
  affects the suspend/resume routines.

Signed-off-by: Robert Chiras <robert.chiras@nxp.com>