[Legacy][TimePasses] allow -time-passes reporting into a custom stream
As a followup to newpm -time-passes fix (D59366), now adding a similar
functionality to legacy time-passes.
Enhancing llvm::reportAndResetTimings to accept an optional stream
for reporting output. By default it still reports into the stream created
by CreateInfoOutputFile (-info-output-file).
Also fixing to actually reset after printing as declared.
Reviewed By: philip.pfaffe
Differential Revision: https://reviews.llvm.org/D59416
llvm-svn: 356824