Perfprofd: Separate symbol offset in samples

Separate out the offset from the start of the sample in the
reporting struct. Parse the data from unwind_symbols.

(cherry picked from commit b84d5fd0c6e67af069fe542149b0fc7d72844e50)

Bug: 73175642
Test: manual
Merged-In: I8910fa826cef0843dd9f98342df4203cb3ebf5c5
Change-Id: I8910fa826cef0843dd9f98342df4203cb3ebf5c5
1 file changed