dt-bindings: anybus-controller: move to staging/ tree

The devicetree bindings for anybus-controller were mistakenly
merged into the main Linux tree. Its driver resides in
staging/, so the bindings belong in staging/ too.

Cc: Greg Kroah-Hartman <[e-mail]>
Fixes: 20a980e957bf ("dt-bindings: anybus-controller: document devicetree binding")
Signed-off-by: Sven Van Asbroeck <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>