The objects in this prebuilt directory can be rebuilt from the source in
$ANDROID/external/qemu/distrib/sdl-1.2.15.

$ cd $ANDROID/external/qemu/distrib/sdl-1.2.15
$ USE_MINGW=1 ./android-configure.sh --prefix=$ANDROID/prebuilts/tools/windowssdl
$ make
$ make install