dt-bindings: display: panel: Rename WL-355608-A8 panel to rg35xx-*-panel

The WL-355608-A8 is a 3.5" 640x480@60Hz RGB LCD display from an unknown
OEM used in a number of handheld gaming devices made by Anbernic.
Previously committed using the OEM serial without a vendor prefix,
however following subsequent discussion the preference is to use the
integrating device vendor and name where the OEM is unknown.

There are 4 RG35XX series devices from Anbernic based on an Allwinner
H700 SoC using this panel, with the -Plus variant introduced first.
Therefore the -Plus is used as the fallback for the subsequent -H,
-2024, and -SP devices.

Alter the filename and compatible string to reflect the convention.

Fixes: 45b888a8 ("dt-bindings: display: panel: Add WL-355608-A8 panel")
Signed-off-by: Ryan Walklin <ryan@testtoast.com>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240904012456.35429-2-ryan@testtoast.com