Supress cmake warning (#931)

Not providing VERSION to "project" command will cause a warning.

Since this project's version is loaded from other files, this policy will help suppress the warning generated by cmake.
This policy is set because we can't provide "VERSION" in "project" command.
Use `cmake --help-policy CMP0048` for more information
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6999292..983e839 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -4,6 +4,11 @@
 # support 2.8.7.
 cmake_minimum_required(VERSION 2.8.6)
 
+# Since this project's version is loaded from other files, this policy
+# will help suppress the warning generated by cmake.
+# This policy is set because we can't provide "VERSION" in "project" command.
+# Use `cmake --help-policy CMP0048` for more information.
+cmake_policy(SET CMP0048 NEW)
 project(brotli C)
 
 if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)