dts: smbus: Simplify the description of the binding

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

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

Author: rruuaanng

dts/bindings/smbus/intel,pch-smbus.yaml

@@ -1,7 +1,7 @@
 # Copyright (c) 2022 Intel Corporation
 # SPDX-License-Identifier: Apache-2.0
 
-description: Intel Platform Controller Hub SMBus node
+description: Intel Platform Controller Hub SMBus
 
 compatible: "intel,pch-smbus"