[Sema][ObjC] Fix a bug where -Wunguarded-availability was emitted at the wrong location

Differential revision: https://reviews.llvm.org/D33250

rdar://32294954

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@303562 91177308-0d34-0410-b5e6-96231b3b80d8
(cherry picked from commit e86bb98b9e798be5ffa8b045fa9a381bebc89a35)
2 files changed