LTO: Add missing target triple from r218784

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218786 91177308-0d34-0410-b5e6-96231b3b80d8

Author: dexonsmith

test/LTO/diagnostic-handler-remarks.ll

@@ -28,6 +28,8 @@
 ; NM-NOT: foo
 ; NM: main
 
+target triple = "x86_64-apple-darwin"
+
 define i32 @foo() {
   ret i32 7
 }