Reports written to disk don't contain the strings used, which will
make this report unusable if there are strings that don't show up
again. We should always include the strings, so this option is
removed entirely.
Also, we hard-coded the wrong number of fields when pulling
ModemActivityInfo. There are actually 10 fields, not 6.
Bug: 79601503
Test: Tested unit-tests pass on marlin-eng.
Change-Id: I6834b096ced77418a9cc2ddd79b08d1c9c447fae
56ae0d9a48