Temporarily print the size of all

variable-length fields in StaLinkLayerStats.

Will be used to verify whether
abnormally large instances of this class
can cause getLinkLayerStats to fail with
an IllegalArgumentException.

Bug: 324519882
Test: Manual test:
       1. Reboot device
       2. Connect to wifi
       3. Verify logged link layer stats
Change-Id: I9378c7e4c2befd98743eb0752fe00cd322110c0f