Fix update_rs_prebuilts.sh so that it works on the latest MacOS.

Change-Id: I11531f2de998fb291fd6d07883d5a103115b09af
diff --git a/update_rs_prebuilts.sh b/update_rs_prebuilts.sh
index 89d7ac1..c08cc79 100755
--- a/update_rs_prebuilts.sh
+++ b/update_rs_prebuilts.sh
@@ -4,7 +4,7 @@
 MY_ANDROID_DIR=$PWD/../../
 cd $MY_ANDROID_DIR
 
-if [ $OSTYPE == 'darwin13' ];
+if [ $OSTYPE == 'darwin13' ] || [ $OSTYPE == 'darwin14' ];
 then
 
   DARWIN=1