Use -Werror in external/fio
am: e3c205cb93

Change-Id: I7b07cd2c8897d87d600c86ea86d9236ff2356c80
diff --git a/Android.bp b/Android.bp
index e2daa40..7aacaf4 100644
--- a/Android.bp
+++ b/Android.bp
@@ -31,6 +31,7 @@
         "-D_FILE_OFFSET_BITS=64",
         "-O3",
         "-Wall",
+        "-Werror",
         "-Wdeclaration-after-statement",
         "-Wwrite-strings",
         "-ffast-math",