Tuner Default HAL Fix bug in TS size calculation

The variable mPesSizeLeft is sometimes being set to a negative value
when it reads from TS data because of conversions from our int8_t vector. This is incorrect, as these sizes are defined to always be positive. Our vectors cannot easily be changed due to our AIDL interfaces, but the SizeLeft variable can be made unsigned to fix the issue.

Bug: 237819905
Test: Manually with cuttlefish and TS input to the DVR with
large values for size bytes. Can also manually test the
result of similar C++ expression to show the behavior.

Change-Id: Iae925cc3c505891b732434fb7c3ffadf7af95411