Camera API1/2: don't register the same listener multiple times

FrameProcessorBase allows register the same metadata result listener multiple
times with the same range IDs, which causes the same metadata result is
delivered multiple times for the same listener. This is problematic as client
like ZslProcessor's updateStream is called multiple times between captures, and
each updateStream calls registerListener unconditionally. The the ZSL metadata
result queue will be flooded with same metadata result multiple times and the
number of same result will keep growing until the queue is full.

Change-Id: I2ff7808e5dce61068a7111e7fbbce2aba95198cd