libFuzzer, OpenBSD support

Summary:
- Enabling libfuzzer on OpenBSD
- OpenBSD can t support asan, msan ... the tests can t be run.

Patch by David CARLIER

Reviewers: eugenis, phosek, vitalybuka

Reviewed By: vitalybuka

Subscribers: srhines, mgorny, krytarowski, llvm-commits, #sanitizers

Differential Revision: https://reviews.llvm.org/D44877

llvm-svn: 329631
diff --git a/compiler-rt/lib/fuzzer/FuzzerExtFunctionsWeak.cpp b/compiler-rt/lib/fuzzer/FuzzerExtFunctionsWeak.cpp
index 7c47dfa..a4e56fc 100644
--- a/compiler-rt/lib/fuzzer/FuzzerExtFunctionsWeak.cpp
+++ b/compiler-rt/lib/fuzzer/FuzzerExtFunctionsWeak.cpp
@@ -13,7 +13,8 @@
 // to clients right now.
 //===----------------------------------------------------------------------===//
 #include "FuzzerDefs.h"
-#if LIBFUZZER_LINUX || LIBFUZZER_NETBSD || LIBFUZZER_FUCHSIA || LIBFUZZER_FREEBSD
+#if LIBFUZZER_LINUX || LIBFUZZER_NETBSD || LIBFUZZER_FUCHSIA ||                \
+    LIBFUZZER_FREEBSD || LIBFUZZER_OPENBSD
 
 #include "FuzzerExtFunctions.h"
 #include "FuzzerIO.h"
@@ -51,4 +52,4 @@
 
 } // namespace fuzzer
 
-#endif // LIBFUZZER_LINUX || LIBFUZZER_NETBSD || LIBFUZZER_FUSCHIA || LIBFUZZER_FREEBSD
+#endif