Use integers instead of NULL.

git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@153941 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp b/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp
index 181d6d0..be9f427 100644
--- a/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp
+++ b/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp
@@ -861,15 +861,15 @@
 
     user_id_t dyn_id = GetSectionIndexByType(SHT_DYNAMIC);
     if (!dyn_id)
-        return NULL;
+        return 0;
 
     SectionList *section_list = GetSectionList();
     if (!section_list)
-        return NULL;
+        return 0;
 
     Section *dynsym = section_list->FindSectionByID(dyn_id).get();
     if (!dynsym)
-        return NULL;
+        return 0;
 
     ELFDynamic symbol;
     DataExtractor dynsym_data;