[ASan] fixes for Android build

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@172800 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/asan/asan_linux.cc b/lib/asan/asan_linux.cc
index 1606ab2..845493d 100644
--- a/lib/asan/asan_linux.cc
+++ b/lib/asan/asan_linux.cc
@@ -127,7 +127,7 @@
 }
 #else
 void ReadContextStack(void *context, uptr *stack, uptr *ssize) {
-  return UNIMPLEMENTED();
+  UNIMPLEMENTED();
 }
 #endif