Remove falsing collection for simpin screen.

When falsing event occurs, it invokes
StatusBarKeyguardViewManager#reset. There is no need to call show again
if the bouncer is already showing. This will prevent a flicker of the
sim screen.

Fixes: 298140114
Fixes: 295116465
Test: tap screen on sim pin screen.
Test: reset device to see the sim pin screen.

Change-Id: Ie4b96eed41e157b882025fc0dca8a9b661cc68de