Fix building on modern versions of Xcode and OS X.

Add the build options to support the most recent versions of XCode and
add 10.9 to the list of OS X SDKs which the AOSP code can be built with.

Based on patch from https://groups.google.com/d/msg/android-building/kePgJmYBUdM/0C_d1OZflvcJ



Change-Id: I97ffe45d3c54a095952a4ac6accb938623b8fa1e
Signed-off-by: Al Sutton <al@funkyandroid.com>