Revert "lshal: close fd before joining thread"

This reverts commit b9d19c87.

Reason of revert: will sometimes cause `lshal debug` to produce
no output at all.

Bug: 111997867
Test: while true; do date; lshal debug android.hardware.health.storage@1.0::IStorage/default; done

Change-Id: I31062b479ea8a9f1c5b94a1ad0969bc5e2e92cd3