Adding privacy tags to graphicsstats proto.

Creating a copy of the graphicsstats proto so that one can be tagged
with privacy annotations and the other can be used internally while
still using the protobuf-cpp-lite library.

Bug: 72570104
Test: flash device and check incident output
Merged-In: I2d72e7bd17689c1401a16d5a13956e6528ddb525
Change-Id: I0a46ee6cc463b133925be1cf8dee8cf3d107930c