Add warning messages to buildit/testit about their upcoming removal

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@292181 91177308-0d34-0410-b5e6-96231b3b80d8

lib/buildit

@@ -6,6 +6,11 @@
 
 set -e
 
+echo "---------- WARNING ----------"
+echo "buildit is no longer supported and will be removed in the next week!"
+echo "please contact the libc++ maintainers if you have any concerns"
+echo ""
+
 if [ `basename $(pwd)` != "lib" ]
 then
     echo "current directory must be lib"
@@ -177,3 +182,8 @@ if [ -z "$RC_XBS" ]
 then
     rm *.o
 fi
+
+echo "---------- WARNING ----------"
+echo "buildit is no longer supported and will be removed in the next week!"
+echo "please contact the libc++ maintainers if you have any concerns"
+echo ""

test/testit

@@ -177,4 +177,7 @@ echo "                       +   ----"
 echo "total number of tests    : $(($FAIL+$PASS))"
 echo "****************************************************"
 
+echo "---------- WARNING ----------"
+echo "testit is no longer supported and will be removed in the future"
+
 exit $FAIL