maxfg_logging: add unix time in learning event

Bug: 341184876
Test: learning event log has new field 'TS:666c55e1'
Change-Id: Id9907969f07614c7be1c50328e541529c2082ab0
Merged-In: I587282ede5602588f14c4b554686ca15f1c63bd3
Signed-off-by: Spade Lee <[email protected]>
1 file changed