Revert "libsnapshot callstack files readable by dumpstate"

This reverts commit faa49d1d0052e074606d88cc56638b573d6e5fb0.

Reason for revert: Callstack should not be logged.

Test: none
Bug: 148818798

Change-Id: Ie5506ae0c7408e255a464b2f403d0a47d272229e
1 file changed