CMake: Fix mingw32 build.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@113677 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/CMakeLists.txt b/CMakeLists.txt
index fdc7755..5577e31 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -88,13 +88,15 @@
   if( LLVM_LINK_COMPONENTS )
     llvm_config(${name} ${LLVM_LINK_COMPONENTS})
   endif( LLVM_LINK_COMPONENTS )
-  get_system_libs(llvm_system_libs)
-  if( llvm_system_libs )
-    target_link_libraries(${name} ${llvm_system_libs})
-  endif( llvm_system_libs )
   if (LLVM_COMMON_LIBS)
     target_link_libraries(${name} ${LLVM_COMMON_LIBS})
   endif()
+  if( NOT MINGW )
+    get_system_libs(llvm_system_libs)
+    if( llvm_system_libs )
+      target_link_libraries(${name} ${llvm_system_libs})
+    endif()
+  endif()
   add_dependencies(${name} ClangDiagnosticCommon)
   if(MSVC)
     get_target_property(cflag ${name} COMPILE_FLAGS)