Rename the 'Attributes' class to 'Attribute'. It's going to represent a single attribute in the future.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170502 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/Dwarf.cpp b/lib/Support/Dwarf.cpp
index de70b0c..839dd84 100644
--- a/lib/Support/Dwarf.cpp
+++ b/lib/Support/Dwarf.cpp
@@ -249,7 +249,7 @@
   case DW_AT_APPLE_property:             return "DW_AT_APPLE_property";
   case DW_AT_APPLE_objc_complete_type:   return "DW_AT_APPLE_objc_complete_type";
 
-    // DWARF5 Fission Extension Attributes
+    // DWARF5 Fission Extension Attribute
   case DW_AT_GNU_dwo_name:               return "DW_AT_GNU_dwo_name";
   case DW_AT_GNU_dwo_id:                 return "DW_AT_GNU_dwo_id";
   case DW_AT_GNU_ranges_base:            return "DW_AT_GNU_ranges_base";