Revert "apq8064-common: Delay sensor init"

This reverts commit ed0b5d68120f1656491431d35dbed12f8662055c.

Change-Id: Ib749696e175e8bf5754c76b3bdfbfad9ba484857
init: Ensure the modem bridge is up before triggering late_start

Some daemons in late_start depend on the firmware images being
loaded. Sensors, in particular, will choke and misbehave is DSPS
isn't loaded. Wait for a sign that the bridge is up before wrapping
up post-fs-data.

Change-Id: Id4875828bc35ab95a2499ce652a49d100b4e8586