Change license of BUILD.gn to GPLv2.
This matches the rest of the Hafnium driver code in this repository.
Change-Id: I84785b5390c21a90acb524e63d3cdf96356667c0
diff --git a/BUILD.gn b/BUILD.gn
index 6c7d688..3739c28 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -1,16 +1,13 @@
# Copyright 2019 The Hafnium Authors.
#
-# 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
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# version 2 as published by the Free Software Foundation.
#
-# https://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.
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
import("//build/linux/linux.gni")