Correct standalone config to build llvm for windows

Change-Id: Iee736d18cef131647802b212a0c5dcc6b130fbe0

Author: lwesiers

CMakeLists.txt

@@ -66,8 +66,10 @@ set(LLVM_BUILD_RUNTIME true CACHE BOOL "desc" FORCE)
 set(LLVM_ENABLE_TERMINFO false CACHE BOOL "desc" FORCE)
 set(LLVM_BUILD_LLVM_DYLIB false CACHE BOOL "desc" FORCE)
 
-if(BUILD_PACKAGE)
-  set(LLVM_BUILD_LLVM_DYLIB true CACHE BOOL "desc" FORCE)
+if(DEFINED BUILD_PACKAGE)
+  if(NOT WIN32)
+    set(LLVM_BUILD_LLVM_DYLIB true CACHE BOOL "desc" FORCE)
+  endif()
   set(LLVM_BUILD_TOOLS false CACHE BOOL "desc" FORCE)
 endif()