Populate `ro.boot.debug.sf.nobootanimation` from `android.bootanim`

emulator passes `android.bootanim=0` in the kernel
command line to disable boot animation.

Bug: 182336906
Test: boot emulator with -np-boot-anim
Signed-off-by: Roman Kiryanov <rkir@google.com>
Change-Id: Id89a6c92dd4724cac414ffbf8ee731b2bfcc7195