Stop presence checking for tags when reader mode is disabled

Presence checking prevents the tag from getting disconnected for a
dedicated time even if the tag is out of range. While enabling reader mode,
users are allowed to set a custom value for the presence checking delay.
This effect should also be disabled, when the mode is disabled.

Test: Sample application; enable/disable Reader Mode
Bug: 70697778
Change-Id: I247f17644b002c60d5ca3624b12021f64a042e97
3 files changed