Merge pull request #2098 from RedDwarf69/v1.x

CMake: Support <PackageName>_ROOT

Author: gabime

CMakeLists.txt

@@ -1,6 +1,6 @@
 # Copyright(c) 2019 spdlog authors Distributed under the MIT License (http://opensource.org/licenses/MIT)
 
-cmake_minimum_required(VERSION 3.10)
+cmake_minimum_required(VERSION 3.10...3.21)
 
 # ---------------------------------------------------------------------------------------
 # Start spdlog project
@@ -15,13 +15,6 @@ message(STATUS "Build spdlog: ${SPDLOG_VERSION}")
 
 include(GNUInstallDirs)
 
-# ---------------------------------------------------------------------------------------
-# Set CMake policies to support later version behaviour
-# ---------------------------------------------------------------------------------------
-if(POLICY CMP0077)
-    cmake_policy(SET CMP0077 NEW) # option() honors variables already set
-endif()
-
 # ---------------------------------------------------------------------------------------
 # Set default build to release
 # ---------------------------------------------------------------------------------------