Revert "dt-bindings: Add vendor prefix for LEGO"

This reverts commit 04e13a5e.

As Ben pointed out, these drivers don't exist in <=4.9.
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/devicetree/bindings/vendor-prefixes.txt

@@ -154,7 +154,6 @@ kosagi	Sutajio Ko-Usagi PTE Ltd.
 kyo	Kyocera Corporation
 lacie	LaCie
 lantiq	Lantiq Semiconductor
-lego	LEGO Systems A/S
 lenovo	Lenovo Group Ltd.
 lg	LG Corporation
 linux	Linux-specific binding