sm8250-common: Switch to SPDX license identifiers

* Might as well be consistent.

Change-Id: Ib95789a0286785ba3b0b6df265291e87a13d2ef8

BoardConfigCommon.mk

@@ -1,17 +1,7 @@
 
 # Copyright (C) 2018 The LineageOS Project
 #
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
 #
 
 BUILD_BROKEN_DUP_RULES := true