Revert "[serialization] Reject loading a module with the wrong case."

This reverts commit r22818, which caused
to fail.

Swift SVN r22822

include/swift/Serialization/ModuleFile.h

@@ -64,9 +64,6 @@ class ModuleFile : public LazyMemberLoader {
   llvm::BitstreamCursor SILCursor;
   llvm::BitstreamCursor SILIndexCursor;
 
-  /// The name of the module.
-  StringRef Name;
-
   /// The data blob containing all of the module's identifiers.
   StringRef IdentifierData;
 
@@ -481,11 +478,6 @@ public:
     return ModuleInputBuffer->getBufferIdentifier();
   }
 
-  /// Returns the module name as stored in the serialized data.
-  StringRef getModuleName() const {
-    return Name;
-  }
-
   /// AST-verify imported decls.
   ///
   /// Has no effect in NDEBUG builds.