store/encrypt: Work around possible ipfs bug.
store/encrypt: Work around possible ipfs bug.

Calling Seek(0, SEEK_END) twice on an ipfs DAGReadSeeker causes the second
Seek to return 0 - which in turn causes a not very descriptive "EOF" in brig.

Further investigation and a minimal testcase remains to be done.

disorganizer/brig,disorganizer/brig