--prefix=../$DESTDIR/$ARCH
You are likely having an issue with the relative path. It's generally better (if not easier) to use the full path to your install root.
One thing you can try, if this is the issue, is to expand the path and try again ... for e.g.
export INSTALL_ROOT=$(cd ../libogg-built/i386; pwd)
./configure ...
...
--prefix="${INSTALL_ROOT}"
Let us know if that helps! Configure scripts can be very finicky.
Update: Nevermind, it's much more simpler in this case I just realized after hitting submit the first time:
CXX="xcrun --sdk iphonesimulator clang++ -arch $ARCH $IOSMV" \
./configure \
#--host=x86_64-apple-darwin \
--prefix=../$DESTDIR/$ARCH
;;
... you cannot have an #-to-end-of-line comment when you are continuing a command onto multiple lines. Just remove #--host=x86_64-apple-darwin \
and you should be set.