Explicitly set policy to new

Author: boomanaiden154

cmake/Modules/CMakePolicy.cmake

@@ -1,5 +1,11 @@
 # CMake policy settings shared between LLVM projects
 
+# CMP0116: Ninja generators transform `DEPFILE`s from `add_custom_command()`
+# New in CMake 3.20. https://cmake.org/cmake/help/latest/policy/CMP0116.html
+if(POLICY CMP0116)
+  cmake_policy(SET CMP0116 NEW)
+endif()
+
 # MSVC debug information format flags are selected via
 # CMAKE_MSVC_DEBUG_INFORMATION_FORMAT, instead of
 # embedding flags in e.g. CMAKE_CXX_FLAGS_RELEASE.