Fix build by converting from bionic to elfutils version of elf.h

Change-Id: I70a3b6fedae6d290a4f01d4ae8fdd726b8aaa90f
diff --git a/runtime/elf_utils.h b/runtime/elf_utils.h
index f160dc4..ce8587b 100644
--- a/runtime/elf_utils.h
+++ b/runtime/elf_utils.h
@@ -17,6 +17,8 @@
 #ifndef ART_RUNTIME_ELF_UTILS_H_
 #define ART_RUNTIME_ELF_UTILS_H_
 
+#include <sys/cdefs.h>
+
 // Explicitly include elf.h from elfutils to avoid Linux and other dependencies.
 #include "../../external/elfutils/0.153/libelf/elf.h"