fixed a compiler error as description in

https://lab.llvm.org/buildbot/#/builders/216/builds/9977

XCOFFOtFile.cpp: error C3487: 'unsigned long': all return expressions must deduce to the same type: previously it was 'uintptr_t'

llvm/lib/Object/XCOFFObjectFile.cpp

@@ -802,7 +802,7 @@ XCOFFObjectFile::getSectionByType(XCOFF::SectionTypeFlags SectType) const {
     for (const auto &Sec : Sections)
       if (Sec.getSectionType() == SectType)
         return reinterpret_cast<uintptr_t>(&Sec);
-    return 0ul;
+    return reinterpret_cast<uintptr_t>(0ul);
   };
   if (is64Bit())
     DRI.p = GetSectionAddr(sections64());