Perfprofd: Refactor protobuf I/O

Move to its own compilation unit.

(cherry picked from commit d0aac2583c77d76f4b78a500d626b5a2a03c3e05)

Bug: 73175642
Test: mmma system/extras/perfprofd
Merged-In: Iad9ddfe5ea84df9fa1fe27a367ec19aa37162c00
Change-Id: Iad9ddfe5ea84df9fa1fe27a367ec19aa37162c00
6 files changed