Add copyright notice to ios.cmake toolchain file

Author: SRSaunders

bldsys/toolchain/ios.cmake

@@ -1,3 +1,24 @@
+#[[
+
+ Copyright (c) 2026, Francesco Giancane
+ Copyright (c) 2026, Stephen Saunders
+
+ SPDX-License-Identifier: Apache-2.0
+
+ 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.
+
+ ]]
+
 # As per upstream CMake recommendation in https://gitlab.kitware.com/cmake/cmake/-/issues/27661
 # for iOS we can use a toolchain file to augment search paths and simplify command line
 #