Fix up one last test for the OBJC_CLASS_REF change.

Author: DougGregor

test/IRGen/MachO-objc-sections.swift

@@ -21,7 +21,7 @@ class D {
 // CHECK-MACHO: @"$S4main1CCMf" = {{.*}}, section "__DATA,__objc_data, regular"
 // CHECK-MACHO: @"\01l_OBJC_LABEL_PROTOCOL_$_P" = {{.*}}, section "__DATA,__objc_protolist,coalesced,no_dead_strip"
 // CHECK-MACHO: @"\01l_OBJC_PROTOCOL_REFERENCE_$_P" = {{.*}}, section "__DATA,__objc_protorefs,coalesced,no_dead_strip"
-// CHECK-MACHO: @"OBJC_CLASS_REF_$_I" = {{.*}}, section "__DATA,__objc_classrefs,regular,no_dead_strip"
+// CHECK-MACHO: @"\01l_OBJC_CLASS_REF_$_I" = {{.*}}, section "__DATA,__objc_classrefs,regular,no_dead_strip"
 // CHECK-MACHO: @"\01L_selector(init)" = {{.*}}, section "__DATA,__objc_selrefs,literal_pointers,no_dead_strip"
 // CHECK-MACHO: @objc_classes = {{.*}}, section "__DATA,__objc_classlist,regular,no_dead_strip"
 // CHECK-MACHO: @objc_categories = {{.*}}, section "__DATA,__objc_catlist,regular,no_dead_strip"