When daemonizing perfetto, SIGINT should be sent to ensure clean
shutdown.
Denial:
12-06 11:12:16.566 3099 3099 I sh : type=1400 audit(0.0:462): avc: denied { signal } for scontext=u:r:shell:s0 tcontext=u:r:perfetto:s0 tclass=process permissive=1
Test: m
Test: flash walleye
Test: SIGINT perfetto from shell
Change-Id: I8d34b447ea90c315faf88f020f1dfc49e4abbcce
