extras/ios: fix build script
extras/ios: fix build script

(cherry picked from commit d32f040df7c85f9331cf5f5aa6438a84e2ad8360)

jomanmuk/vlc-2.2,jomanmuk/vlc-2.2,jomanmuk/vlc-2.2,jomanmuk/vlc-2.2,jomanmuk/vlc-2.2,jomanmuk/vlc-2.2,jomanmuk/vlc-2.2