GnssMeasurementsListener - Fix indexing, add & remove

Safer indexing open requests by IBinder instead of IInterface
Covers GnssNavigationMessage as well.
Also dumping currently open GnssMeasurement & NavMsg requests

Bug: 71917458
Test: Able to repro issue consistently before, fixed after
 logs look as expected as well, on Pixel 2

Change-Id: I2e4722a23355295a5f597541f31a3b77534cadd7