Revert "Add a CMake option to link the C runtime statically."

This reverts commit 44dc43ab04.

CMakeLists.txt

@@ -1,16 +1,11 @@
 cmake_minimum_required(VERSION 2.4.4...3.15.0)
 set(CMAKE_ALLOW_LOOSE_LOOP_CONSTRUCTS ON)
 
-if(POLICY CMP0091)
-    cmake_policy(SET CMP0091 NEW)
-endif()
-
 project(zlib C)
 
 set(VERSION "1.3.0.1")
 
 option(ZLIB_BUILD_EXAMPLES "Enable Zlib Examples" ON)
-option(ZLIB_STATIC_LINK_CRT "Link the MSVC runtime library statically" OFF)
 
 set(INSTALL_BIN_DIR "${CMAKE_INSTALL_PREFIX}/bin" CACHE PATH "Installation directory for executables")
 set(INSTALL_LIB_DIR "${CMAKE_INSTALL_PREFIX}/lib" CACHE PATH "Installation directory for libraries")
@@ -83,24 +78,12 @@ if(NOT CMAKE_CURRENT_SOURCE_DIR STREQUAL CMAKE_CURRENT_BINARY_DIR)
 endif()
 
 set(ZLIB_PC ${CMAKE_CURRENT_BINARY_DIR}/zlib.pc)
-configure_file(${CMAKE_CURRENT_SOURCE_DIR}/zlib.pc.cmakein
-        ${ZLIB_PC} @ONLY)
-configure_file(${CMAKE_CURRENT_SOURCE_DIR}/zconf.h.cmakein
-       ${CMAKE_CURRENT_BINARY_DIR}/zconf.h @ONLY)
+configure_file( ${CMAKE_CURRENT_SOURCE_DIR}/zlib.pc.cmakein
+		${ZLIB_PC} @ONLY)
+configure_file(	${CMAKE_CURRENT_SOURCE_DIR}/zconf.h.cmakein
+		${CMAKE_CURRENT_BINARY_DIR}/zconf.h @ONLY)
 include_directories(${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_SOURCE_DIR})
 
-if(POLICY CMP0091)
-    # CMake >= 3.15 has CMAKE_MSVC_RUNTIME_LIBRARY to set the MSVCC runtime library
-    if(WIN32 AND CMAKE_GENERATOR MATCHES "Visual Studio .*|NMake .*")
-        if(ZLIB_STATIC_LINK_CRT)
-            message(STATUS "Configuring to link the MSVC runtime library statically")
-            set(CMAKE_MSVC_RUNTIME_LIBRARY "MultiThreaded$<$<CONFIG:Debug>:Debug>")
-        else()
-            message(STATUS "Configuring to link the MSVC runtime library dynamically")
-            set(CMAKE_MSVC_RUNTIME_LIBRARY "MultiThreaded$<$<CONFIG:Debug>:Debug>DLL")
-        endif()
-    endif()
-endif()
 
 #============================================================================
 # zlib