dt-bindings: panel-simple-dsi: move LG 5" HD TFT LCD panel into DSI yaml

Originally was in the panel-simple, but belongs to panel-simple-dsi.

See arch/arm/boot/dts/nvidia/tegra114-roth.dts for more details.

Resolves the following warning:
```
arch/arm/boot/dts/tegra114-roth.dt.yaml: panel@0: 'reg' does not match any of the regexes: 'pinctrl-[0-9]+'
From schema: Documentation/devicetree/bindings/display/panel/panel-simple.yaml
```

Fixes: 310abcea76e9 ("dt-bindings: display: convert simple lg panels to DT Schema")
Signed-off-by: David Heidelberg <[e-mail]>
Acked-by: Krzysztof Kozlowski <[e-mail]>
Acked-by: Jessica Zhang <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Neil Armstrong <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

Documentation/devicetree/bindings/display/panel/panel-simple-dsi.yaml

···
       - lg,acx467akm-7
         # LG Corporation 7" WXGA TFT LCD panel
       - lg,ld070wx3-sl01
+        # LG Corporation 5" HD TFT LCD panel
+      - lg,lh500wx1-sd03
         # One Stop Displays OSD101T2587-53TS 10.1" 1920x1200 panel
       - osddisplays,osd101t2587-53ts
         # Panasonic 10" WUXGA TFT LCD panel

Documentation/devicetree/bindings/display/panel/panel-simple.yaml

···
       - lemaker,bl035-rgb-002
         # LG 7" (800x480 pixels) TFT LCD panel
       - lg,lb070wv8
-        # LG Corporation 5" HD TFT LCD panel
-      - lg,lh500wx1-sd03
         # LG LP079QX1-SP0V 7.9" (1536x2048 pixels) TFT LCD panel
       - lg,lp079qx1-sp0v
         # LG 9.7" (2048x1536 pixels) TFT LCD panel