phosphor-logging: srcrev bump 31eed996da..935a25e2be

Matt Spinler (6):
      PEL: Refactor the test data factory
      PEL: Add 3 more sections to the test PEL data
      PEL: Enhance the real PEL test
      PEL: Stream: Don't use references for << ops
      PEL: Fix typo in subsystem ID list
      PEL: Allow default AdditionalData construction

(From meta-phosphor rev: 3cbe0bc1eeccde99236d042818879985195e790f)

Change-Id: I7d2946d60a891ff74a63c9892acb4418d6ef8e05
Signed-off-by: Andrew Geissler <openbmcbump-github@yahoo.com>
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>