Use getValue instead of getAddress in a few MachO only cases.

In MachO the value of the symbol is always the address, so we can use the
simpler function.

llvm-svn: 241364
diff --git a/llvm/lib/Object/MachOObjectFile.cpp b/llvm/lib/Object/MachOObjectFile.cpp
index 4255ed7..53ea444 100644
--- a/llvm/lib/Object/MachOObjectFile.cpp
+++ b/llvm/lib/Object/MachOObjectFile.cpp
@@ -392,9 +392,7 @@
 }
 
 uint64_t MachOObjectFile::getCommonSymbolSizeImpl(DataRefImpl DRI) const {
-  uint64_t Value;
-  getSymbolAddress(DRI, Value);
-  return Value;
+  return getSymbolValue(DRI);
 }
 
 SymbolRef::Type MachOObjectFile::getSymbolType(DataRefImpl Symb) const {
@@ -434,8 +432,7 @@
   if (MachOType & MachO::N_EXT) {
     Result |= SymbolRef::SF_Global;
     if ((MachOType & MachO::N_TYPE) == MachO::N_UNDF) {
-      uint64_t Value;
-      getSymbolAddress(DRI, Value);
+      uint64_t Value = getSymbolValue(DRI);
       if (Value && Value != UnknownAddress)
         Result |= SymbolRef::SF_Common;
     }