dt-binding: can: mcp251xfd: narrow down wildcards in device tree bindings to "microchip,mcp251xfd"

The wildcard should be narrowed down to prevent existing and future devices
that are not compatible from matching. It is very unlikely that incompatible
devices will be released that do not match the wildcard.

This is the documentation part of the commit.

Discussion Reference: https://lore.kernel.org/r/CAMuHMdVkwGjr6dJuMyhQNqFoJqbh6Ec5V2b5LenCshwpM2SDsQ@mail.gmail.com



Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Thomas Kopp <thomas.kopp@microchip.com>
Link: https://lore.kernel.org/r/20200930091423.755-2-thomas.kopp@microchip.com


[mkl: rename file, too]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>