dts: usb: Simplify the description of the binding

Remove redundant descriptions in USB bindings, such
as "... node".

Signed-off-by: James Roy <rruuaanng@outlook.com>

Author: rruuaanng

dts/bindings/usb/snps,designware-usb.yaml

@@ -1,7 +1,7 @@
 # Copyright (c) 2019 Intel Corporation
 # SPDX-License-Identifier: Apache-2.0
 
-description: Synopsys Designware USB Controller node
+description: Synopsys Designware USB controller
 
 compatible: "snps,designware-usb"