Saving space by writing/reading to compressed file instead of raw binary

[siyuanchai1999]

We can directly write to a compressed file using gzwrite in QEMU. When dynamorio read it, it will be using gzread. This will save the space of the output, but may slowdown the write speed due to compression overhead. I am not sure about the trade off is not yet clear, so we need some testing on that.

Where qemu performs write: https://github.com/xlab-uiuc/qemu_ECPT/blob/de63a5a4f6025cebef8d4de53e18b47ab8fefff8/tests/plugin/execlog.c#L223C12-L223C18
where dynamorio performs read: https://github.com/xlab-uiuc/dynamorio/blob/b08d8603b4350fc47ba38810f208dd852db01498/clients/drcachesim/reader/qemu_file_reader.cpp#L283