build: clean up some unnecessary cached variables

The CMAKE_<LANG>_ARCHIVE_FINISH rule doesn't need to be cleared for Darwin
static libraries.  Avoid resetting the variables in the SIP case.  If
CMAKE_RANLIB is cached, then CMake's Ninja generator will invoke ranlib during
installation, not due to the CMAKE_<LANG>_ARCHIVE_FINISH rule.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@342511 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/CMakeLists.txt b/CMakeLists.txt
index d4f1856..f363a51 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -123,9 +123,6 @@
 
       foreach(lang ${languages})
         set(CMAKE_${lang}_CREATE_STATIC_LIBRARY "\"${CMAKE_LIBTOOL}\" -static ${LIBTOOL_NO_WARNING_FLAG} -o <TARGET> <LINK_FLAGS> <OBJECTS>")
-        # Replace the finish target so that ranlib is not invoked on the
-        # archive.
-        set(CMAKE_${lang}_ARCHIVE_FINISH "")
       endforeach()
     endif()
 
@@ -136,8 +133,6 @@
         foreach(cmd ${CMAKE_${lang}_CREATE_STATIC_LIBRARY})
           list(APPEND CMAKE_${lang}_CREATE_STATIC_LIBRARY_NEW "${dyld_envar} ${cmd}")
         endforeach()
-        set(CMAKE_${lang}_CREATE_STATIC_LIBRARY ${CMAKE_${lang}_CREATE_STATIC_LIBRARY_NEW})
-        set(CMAKE_${lang}_ARCHIVE_FINISH " ")
       endforeach()
     endif()
   endif()