init: make CheckPropertyTriggers() more efficient

Previously CheckPropertyTriggers() tried to do the entire property
triggers check with one loop.  However, that would require calling
GetProperty() on all properties for all triggers just in case the
property that is being set is used by a given trigger.

This change first checks that the property being set exists in each
trigger and that its value is set such that the trigger would be
triggered, only then does it check that other property triggers are
set to the right value.

Bug: 143922756
Test: boot
Test: substantially fewer GetProperty() calls from
      CheckPropertyTriggers()

Change-Id: I0228cf47328b31963eaf3fc689fb60f711532df4