Add sync and fence tracepoints to user-visible list of tracepoints.

The 'sync' tracepoint was updated to be 'fence' in kernel 4.9, so this
change also adds that one to the list.

Bug: 79935503
Test: Took a trace using 'sync' in user mode and saw the tracepoints
being saved.

Change-Id: I793c6f54cd9364f33853983f8c5dfb28b98c2708
Merged-In: I793c6f54cd9364f33853983f8c5dfb28b98c2708