rdr: When regulated leaves data in the queue at EOF

[nthallen]

To reproduce:

• Run instrument and note MFCtr when issuing 'Quit' (e.g. 602)
• saverun, run playback and note MFCtr when telemetry stops (e.g. 543)

Note that if you switch to fast forward mode (Telemetry FF), it seems to run to the very end (e.g. 602).

I have verified that the data in question is not in bfr, so rdr is the most likely suspect

[nthallen]

rdr apparently stops at the end of the penultimate LOG file, but only when regulated.

[nthallen]

Resolved by a845946