Remove __DATE__/__TIME__ from init and debuggerd

Keeping these means that every build has different init and debuggerd
binaries, even if the source was the same. So OTAs that don't touch
these sources would still need to update the binaries.

Both of these messages are only informational, so can be safely removed.
Bootchart already encodes build-specific information from the system
properties.

Bug: 24204119
Change-Id: I7ebd65a20a3e031e7528c9f741616e20b3cd7446
(cherry picked from commit 30622bbb)