[PATCH 1/4] lib-compression: wrap *_read() in for(;;) loop (reindent only)

[PATCH 1/4] lib-compression: wrap *_read() in for(;;) loop (reindent only)

Prepare for the next commit: wrap the body of i_stream_lz4_read(),
i_stream_bzlib_read(), and i_stream_zlib_read() in a for(;;) loop.
No logic change; all paths still return on the first iteration.
Separating the indent churn makes the actual fix easier to review.

Gbp-Pq: Name 0001-lib-compression-wrap-_read-in-for-loop-reindent-only.patch